Sex: Male

  • Doctor of Philosophy in Chemistry (Chemical Biology), University of Alberta, 2021
  • Master of Science in Microbiology and Biotechnology, University of Alberta, 2013
  • Bachelor of Science in Biology, University of the Philippines Los Baños, 2005

Field of Specialization:

Chemical Biology


Article title: Screening, characterization, and isolation of pigments from bacteria in
mesophotic depths of the Benham Bank Seamount, Philippine Rise Region.
Authors: Christopher G. Batbatan, Albert Remus R. Rosana, Kleinberg X. Fernandez, Saul M. Rojas, Hildie Maria E. Nacorda, Asuncion K. Raymundo, and Nacita B. Lantican
Publication title: Philippine Journal of Science 151(2): 615-641, April 2022

The exploration for pigment-producing bacteria and structurally novel pigment continues to increase, and the marine environment has recently become an attractive research site for these investigations because of its rich yet untapped biodiversity. In this study, 16S rRNA gene sequencing and HPLC (high-performance liquid chromatography) profiling of the microbial pigments produced by marine heterotrophic bacteria were described. Seven phenotypically distinct isolates of marine pigmented heterotrophic bacteria (MPHB) were isolated from near-bottom waters and coral reef sediments at mesophotic depths of the Benham Bank Seamount – namely, isolates BR14, BR61, BR63, BR100, BR101, BR144, and BR146. Four promising isolates were subjected to 16S rRNA gene sequencing and revealed that strains BR61 and BR100 were related to members of the genus Cytobacillus, whereas isolates BR144 and BR146 clustered with Meridianimaribacter flavus and Pseudoalteromonas rubra, respectively. Growth of the seven isolates on three media – natural sea water (NSW) Reasoner’s 2A (R2A), marine agar (MA), and tryptic soy agar – revealed variable pigment production and growth yield. MA appeared to be a superior substrate, resulting in darker pigmentation and higher biomass yield. Through a liquid-liquid partitioning approach, isolates BR14 and BR100 produced pigments that were acetone-soluble, whereas isolates BR101, BR144, and BR146 are hexane soluble. Moreover, the BR146 red pigment was proposed to be a mixture of putative prodiginine analogs. The putative prodiginines produced by isolate BR146 can stain fabrics, supporting a proof-of-concept that marine bacteria can be utilized as fabric colorants. The data presented here provided new insights into the utilization of local Philippine marine microbial resources for natural marine pigments with industrial applications.
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Article title: Methylene Analogues of Neopetrosiamide as Potential Antimetastatic Agents: Solid-Supported Syntheses Using Diamino Diacids for Pre-Stapling of Peptides with Multiple Disulfides
Authors: Cameron A. Pascoe, Daniel B. Engelhardt, Albert Remus R. Rosana, Marco J. van Belkum, and John C. Vederas
Publication title: Organic Letters (23):9216-9220, 2021

Neopetrosiamide, a 28-residue peptide from Neopetrosia sp., contains three disulfide bonds and hinders mammalian tumor cell invasion. Proper connectivity of disulfide bonds is crucial for activity. Synthetic replacement of single disulfide bridges with methylene bridges gives active analogues. Pre-stapling of one ring enhances the correct formation of the remaining disulfides by reducing isomeric possibilities and possibly initiating the correct 3D fold. Cloning and expression of neopetrosiamide in E. coli affords access to the natural linear peptide.
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Article title: Genomic insights into the antimicrobial and anticancer potential of
Streptomyces isolated from volcanic soils of Mount Mayon, Philippines.
Authors: Kristel Mae P. Oliveros, Albert Remus R. Rosana, Andrew D. Montecillo, Rina B. Opulencia, Arian J. Jacildo, Teofila O. Zulaybar, and Asuncion K. Raymundo
Publication title: Philippine Journal of Science 150(6A):1351-1377, December 2021

Antimicrobial resistance (AMR) poses a global and developmental threat to humanity. The rapid emergence and spread of drug-resistant pathogens resulted in the ineffective use of currently available antibiotics. Therefore, there is a need to continue searching for additional sources of antibiotics, such as actinomycetes, which can potentially harbor unique and effective secondary metabolites. Furthermore, it is interesting to consider poorly explored environments like volcanoes, which can be potential sources of drug leads for medically important natural products. This study reports the antimicrobial activity of actinomycetes isolated from volcanic soil samples collected from Mount Mayon, Albay, Philippines. A total of 13 out of 30 morphologically distinct actinomycete isolates showed antagonistic activity against test microorganisms. Isolate A1-08, the focus of the study, exhibited a wide spectrum of antimicrobial activity against Salmonella enterica, Klebsiella pneumoniae, Staphylococcus aureus, methicillin-resistant S. aureus(MRSA), Candida albicans, Aspergillus niger, and Fusarium sp. Moreover, A1-08 was found to have anti-methicillin resistant S. aureus (MIC = 2.50 mg/mL) and anticancer activity against human colorectal cancer (HCT116) cell line (IC50 = 21.54 μg/mL). Whole-genome sequence-based phylogenetic analysis supported a novel species of Streptomyces closely related to S. olivaceus NRRL B-3009. A total of 48 biosynthetic gene clusters (BGCs) were identified that may be responsible for the biosynthesis of known and potentially novel secondary metabolites. This study concludes that Streptomyces sp. A1-08, a potentially novel species, is a good candidate to produce broad-spectrum antibiotics with anti-MRSA and anti-cancer activities and possibly novel secondary bioactive metabolites of medical and pharmaceutical importance.
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Article title: Selection of entomopathogenic fungus Beauveria bassiana (Deuteromycotina: Hyphomycetes) for the biocontrol of Dendroctonus ponderosae (Coleoptera: Curculionidae, Scolytinae) in Western Canada.
Authors: Albert Remus R. Rosana, Stanley Pokorny, Jennifer G. Klutsch, Cherry Ibarra-Romero, Randy Sanichar, Daniel Engelhardt, Marco J. van Belkum, Nadir Erbilgin, Joerg Bohlmann, Allan L. Carroll & John C. Vederas
Publication title: Applied Microbiology and Biotechnology (105):2541-2557, 2021

The mountain pine beetle, Dendroctonus ponderosae, has infested over ~16 Mha of pine forests in British Columbia killing >50% of mature lodgepole pine, Pinus contorta, trees in affected stands. At present, it is functionally an invasive species in Alberta, killing and reproducing in evolutionarily naïve populations of lodgepole pine (P. contorta), novel jack pine (P. banksiana), and their hybrids. The entomopathogenic fungus Beauveria bassiana has shown some potential as a biocontrol agent of several bark beetle species. In this study, nine isolates of B. bassiana were examined for insect virulence characteristics, including conidiation rate, pigmentation, and infection rate in laboratory-reared D. ponderosae, to assess for their potential as biocontrol agents. The strains were categorized into three phenotypic groups based on pigmentation, conidial density, and myceliation rate. Virulence screening utilizing insect-based agar medium (D. ponderosae and European honeybee Apis mellifera carcasses) revealed no difference in selection of fungal growth. However, infection studies on D. ponderosae and A. mellifera showed contrasting results. In vivo A. mellifera infection model revealed ~5% mortality, representing the natural death rate of the hive population, whereas laboratory-reared D. ponderosae showed 100% mortality and mycosis. The LT50 (median lethal time 50) ranges from 2 to 5 ± 0.33 days, and LT100 ranges from 4 to 6 ± 0.5 days. We discuss the selective advantages of the three phenotypic groups in terms of virulence, pigmentation, conidial abundance, and tolerance to abiotic factors like UV and host tree monoterpenes. These results can further provide insights into the development of several phenotypically diverse B. bassiana strains in controlling the spread of the invasive D. ponderosae in Western Canada.
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Article title: Draft genome sequence of the phosphate-solubilizing
rhizobacterium Burkholderia pseudomultivorans strain MPSB1, isolated from a copper mined-out site.
Authors: Berna Lou L. Aba-Regis, Kristel Mae P. Oliveros, Cherry Ibarra-Romero, Asuncion K. Raymundo, Nelly S. Aggangan, Teofila O. Zulaybar, Albert Remus R. Rosana
Publication title: Microbiology Resource Announcements 10(1): e01304-20, 2021

Burkholderia pseudomultivorans MPSB1 was isolated from a copper mined-out soil sample collected from Mogpog, Marinduque, Philippines. Here, we report the draft genome sequence with predicted gene inventories supporting rhizosphere bioremediation, such as heavy metal tolerance, phosphate solubilization, and siderophore production.
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Article title: RNA helicase-regulated processing of the Synechocystis rimO-crhR operon results in differential cistron expression and accumulation of two sRNAs
Authors: Albert Remus R. Rosana, Denise S. Whitford, Anzhela Migur, Claudia Steglich, Sonya L Kujat-Choy, Wolfgang R. Hess, George W. Owttrim
Publication title: The Journal of Biochemistry 295(19):6372-6386, May 2020

The arrangement of functionally-related genes in operons is a fundamental element of how genetic information is organized in prokaryotes. This organization ensures coordinated gene expression by co-transcription. Often, however, alternative genetic responses to specific stress conditions demand the discoordination of operon expression. During cold temperature stress, accumulation of the gene encoding the sole Asp-Glu-Ala-Asp (DEAD)-box RNA helicase in Synechocystis sp. PCC 6803, crhR (slr0083), increases 15-fold. Here, we show that crhR is expressed from a dicistronic operon with the methylthiotransferase rimO/miaB (slr0082) gene, followed by rapid processing of the operon transcript into two monocistronic mRNAs. This cleavage event is required for and results in destabilization of the rimO transcript. Results from secondary structure modeling and analysis of RNase E cleavage of the rimO-crhR transcript in vitro suggested that CrhR plays a role in enhancing the rate of the processing in an auto-regulatory manner. Moreover, two putative small RNAs are generated from additional processing, degradation, or both of the rimO transcript. These results suggest a role for the bacterial RNA helicase CrhR in RNase E-dependent mRNA processing in Synechocystis and expand the known range of organisms possessing small RNAs derived from processing of mRNA transcripts.
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Article title: Draft Genome Sequence of the Thermophilic Bacterium Bacillus licheniformis SMIA-2, an Antimicrobial- and Thermostable Enzyme-Producing Isolate from Brazilian Soil
Authors: Samara Pinto Custodio Bernardo, Albert Remus R. Rosana, Adriane Nunes de Souza, Sorina Chiorean, Meire Lelis Leal Martins, John C. Vederas
Publication title: Microbiology Resource Announcements 9(17): e00106-20, 2020

Bacillus licheniformis SMIA-2, a thermophilic and thermostable enzyme-producing bacterium, is found to be active against several strains of Staphylococcus aureus and several Bacillus species. Here, we report the 4.30-Mbp draft genome and bioinformatic predictions supporting gene inventories for amylase, protease, cellulase, xylanase, and antimicrobial compound biosynthesis.
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Article title: Isolation and characterization of Serratia marcescens bacteriophages from sewage water.
Authors: Rakesh Coleen Dacayo, Albert Remus R. Rosana, and Lucille C. Villegas
Publication title: Journal of Nature Studies 18(2): 92-107, 2019

Serratia marcescens has been recognized as an opportunistic nosocomial pathogen. The emergence of multidrug-resistant S. marcescens strains, which pose threats to public health, prompts actions to control their growth and dissemination. One of the leading control strategies which has the potential to be used as either an alternative or a supplement to antibiotic treatment is phage therapy. This study was performed to isolate bacteriophages that can be used against S. marcescens, and characterize the isolated phages based on lytic activity and particle morphology. The bacteriophages were obtained from raw sewage through phage enrichment followed by double agar overlay plaque assay. Plaques exhibiting varying morphologies were isolated and purified. Phage isolates designated as P1, P2, P3 and P4 formed turbid plaques while phage P5 formed clear circular plaques surrounded by a large halo. Assessment of the lytic activity of the phages showed that the S. marcescens wild type and seven S. marcescens Tn5-insertional mutants were
susceptible to the five phage isolates. Phages P1, P2 and P3 were able to infect Escherichia coli while only phage P4 was able to infect Salmonella enterica subsp. enterica. Unrelated genera which included Bacillus megaterium, B. subtilis, Staphylococcus aureus, Pseudomonas aeruginosa and Micrococcus luteus were not susceptible to all the phages. Based on the virion size and morphology as revealed by electron microscopic analysis, the possible identity of the phage isolates was deduced following the classification scheme of the International Committee on Taxonomy of Viruses. The five phages may belong to Order
Caudovirales. Phages P1 and P2 having icosahedral-isometric heads with thin, long, noncontractile, flexible tail, may belong to Family Siphoviridae. Phage P3 has icosahedralisometric head with no visible tail which may indicate that it belongs to Family Podoviridae. Phage P5 possesses an icosahedral-isometric head with a neck that is connected to a rigid contractile tail, which may classify it under Family Myoviridae. The results of this study suggest the possible use of the phages as bactericidal agents. Further characterization of the identified phages can be done to fully understand their potential application as biocontrol agents against S. marcescens.
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Article title: Draft Genome Sequences of Six Bacteria Isolated from the Benham Bank, Philippine Rise, Philippines
Authors: Saul M. Rojas, Albert Remus R. Rosana, Andrew D. Montecillo, Mark Dondi M. Arboleda, Hildie Maria E. Nacorda, Nacita B. Lantican
Publication title: Microbiology Resource Announcements 8(29): e00777-19, 2019

We report here the draft genome sequences of six bacteria isolated from the near-bottom waters and surface sediments of the Benham Bank, Philippine Rise, Philippines. These genome sequences represent candidate novel species and/or strains from the families Flavobacteriaceae and Dermacoccaceae and the genera Idiomarina, Bacillus, and Vibrio.
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Article title: Draft Genome Sequence of Enterobacter sp. Strain AD2-3, Isolated from a Postmining Site in Benguet, Philippines
Authors: Jocelyn T. Zarate, Genevieve Mae B. Aquino, Joana Marie C. Cruz, Neilyn O. Villa, and Albert Remus R. Rosana
Publication title: Microbiology Resource Announcements 8(30): e00563-19, 2019

The novel strain Enterobacter sp. strain AD2-3 was isolated from postmining soil samples collected from Antamok mine in Benguet, Philippines. Here, we report a draft of its whole-genome sequence, with predicted gene inventories supporting metal tolerance, nitrogen fixation, phosphate solubilization, and indole acetic acid production.
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Article title: Herbs and spices: Biomarkers of intake based on human intervention studies - A systematic review
Authors: Rosa Vázquez-Fresno, Albert Remus R. Rosana, Tanvir Sajed, Tuviere Onookome-Okome, Noah A. Wishart, David S. Wishart
Publication title: Genes Nutrition 14:1-27, May 2019

Culinary herbs and spices have been used as both food flavoring and food preservative agents for centuries. Moreover, due to their known and presumptive health benefits, herbs and spices have also been used in medical practices since ancient times. Some of the health effects attributed to herbs and spices include antioxidant, anti-microbial, and anti-inflammatory effects as well as potential protection against cardiovascular disease, neurodegeneration, type 2 diabetes, and cancer. While interest in herbs and spices as medicinal agents remains high and their use in foods continues to grow, there have been remarkably few studies that have attempted to track the dietary intake of herbs and spices and even fewer that have tried to find potential biomarkers of food intake (BFIs). The aim of the present review is to systematically survey the global literature on herbs and spices in an effort to identify and evaluate specific intake biomarkers for a representative set of common herbs and spices in humans. A total of 25 herbs and spices were initially chosen, including anise, basil, black pepper, caraway, chili pepper, cinnamon, clove, cumin, curcumin, dill, fennel, fenugreek, ginger, lemongrass, marjoram, nutmeg, oregano, parsley, peppermint and spearmint, rosemary, saffron, sage, tarragon, and thyme. However, only 17 of these herbs and spices had published, peer-reviewed studies describing potential biomarkers of intake. In many studies, the herb or spice of interest was administrated in the form of a capsule or extract and very few studies were performed with actual foods. A systematic assessment of the candidate biomarkers was also performed. Given the limitations in the experimental designs for many of the published studies, further work is needed to better evaluate the identified set of BFIs. Although the daily intake of herbs and spices is very low compared to most other foods, this important set of food seasoning agents should not be underestimated, especially given their potential benefits to human health.
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Article title: Inactivation of the RNA helicase CrhR impacts a specific subset of the transcriptome in the cyanobacterium Synechocystis sp. PCC 6803.
Authors: Jens Georg, Albert Remus R. Rosana, Danuta Chamot, Anzhela Migur, Wolfgang R. Hess, George W. Owttrim
Publication title: RNA biology 16(9): 1205-1214, September 2019

DEAD-box RNA-helicases catalyze the reorganization of structured RNAs and the formation of RNP complexes. The cyanobacterium Synechocystis sp. PCC 6803 encodes a single DEAD-box RNA helicase, CrhR (Slr0083), whose expression is regulated by abiotic stresses that alter the redox potential of the photosynthetic electron transport chain, including temperature downshift. Despite its proposed effect on RNA metabolism and its known relevance in cold-stress adaptation, the reported impact of a CrhR knockout on the cold adaption of the transcriptome only identified eight affected genes. Here, we utilized a custom designed microarray to assess the impact of the absence of CrhR RNA helicase activity on the transcriptome, independent of cold stress. CrhR truncation impacts an RNA subset comprising ~10% of the ncRNA and also ~10% of the mRNA transcripts. While equal numbers of mRNAs showed increased as well as decreased abundance, more than 90% of the ncRNAs showed enhanced expression in the absence of CrhR, indicative of a negative effect on ncRNA transcription or stability. We further tested the effect of CrhR on the stability of strongly responding RNAs that identify examples of post-transcriptional and transcriptional regulation. The data suggest that CrhR impacts multiple aspects of RNA metabolism in Synechocystis.
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Article title: Genomic insights into the draft genome sequence of Bacillus thuringiensis DNG9 isolated from Algerian soil-oil slough.
Authors: Mohamed Seghir Daas, Albert Remus R Rosana, Jeella Z Acedo, Malika Douzane, Farida Nateche, Salima Kebbouche-Gana, John C Vederas
Publication title: Standards in genomic sciences 13:1-25, October 2018

Bacillus thuringiensis is widely used as a bioinsecticide due to its ability to form parasporal crystals containing proteinaceous toxins. It is a member of the Bacillus cereus sensu lato, a group with low genetic diversity but produces several promising antimicrobial compounds. B. thuringiensis DNG9, isolated from an oil-contaminated slough in Algeria, has strong antibacterial, antifungal and biosurfactant properties. Here, we report the 6.06 Mbp draft genome sequence of B. thuringiensis DNG9. The genome encodes several gene inventories for the biosynthesis of bioactive compounds such as zwittermycin A, petrobactin, insecticidal toxins, polyhydroxyalkanoates and multiple bacteriocins. We expect the genome information of strain DNG9 will provide another model system to study pathogenicity against insect pests, plant diseases, and antimicrobial compound mining and comparative phylogenesis among the Bacillus cereus sensu lato group.
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Article title: Biomarker of food intake for assessing the consumption of dairy and egg products
Authors: Linda H Münger, Mar Garcia-Aloy, Rosa Vázquez-Fresno, Doreen Gille, Albert Remus R. Rosana, Anna Passerini, María-Trinidad Soria-Florido, Grégory Pimentel, Tanvir Sajed, David S. Wishart, Cristina Andres Lacueva, Guy Vergères, and Giulia Praticò
Publication title: Genes & nutrition 13: 1-18, 2018

Dairy and egg products constitute an important part of Western diets as they represent an excellent source of high-quality proteins, vitamins, minerals and fats. Dairy and egg products are highly diverse and their associations with a range of nutritional and health outcomes are therefore heterogeneous. Such associations are also often weak or debated due to the difficulty in establishing correct assessments of dietary intake. Therefore, in order to better characterize associations between the consumption of these foods and health outcomes, it is important to identify reliable biomarkers of their intake. Biomarkers of food intake (BFIs) provide an accurate measure of intake, which is independent of the memory and sincerity of the subjects as well as of their knowledge about the consumed foods. We have, therefore, conducted a systematic search of the scientific literature to evaluate the current status of potential BFIs for dairy products and BFIs for egg products commonly consumed in Europe. Strikingly, only a limited number of compounds have been reported as markers for the intake of these products and none of them have been sufficiently validated. A series of challenges hinders the identification and validation of BFI for dairy and egg products, in particular, the heterogeneous composition of these foods and the lack of specificity of the markers identified so far. Further studies are, therefore, necessary to validate these compounds and to discover new candidate BFIs. Untargeted metabolomic strategies may allow the identification of novel biomarkers, which, when taken separately or in combination, could be used to assess the intake of dairy and egg products.
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Article title: Near-complete genome sequence of Ralstonia solanacearum T523 a phylotype I tomato phytopathogen isolated from the Philippines.
Authors: Andrew D. Montecillo, Asuncion K. Raymundo, Irene A. Papa, Genevieve Mae B. Aquino, Arian J. Jacildo, Paul Stothard, Albert Remus R. Rosana
Publication title: Microbiology Resource Announcements 7(12): e01048, September 2018

Ralstonia solanacearum strain T523 is the major phytopathogen causing tomato bacterial wilt in the Philippines. Here, we report the complete chromosome and draft megaplasmid genomes with predicted gene inventories supporting rhizosphere processes, extensive plant virulence effectors, and the production of bioactive signaling metabolites, such as ralstonin, micacocidin, and homoserine lactone.
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Article title: Near complete genome sequence of Streptomyces sp. AC1-42T and AC1-42W isolated from bat guano of Cabalyorisa Cave, Pangasinan, Philippines.
Authors: Marian P. De Leon, A-young Park, Andrew D. Montecillo, Maria Auxilia T. Siringan, Albert Remus R., Song-Gun
Publication title: Microbiology Resource Announcements 7(7): e00904-18, 2018

Streptomyces sp. strains AC1-42T and AC1-42W, isolated from bat guano from Cabalyorisa Cave, Mabini, Pangasinan, Philippines, are active against Bacillus subtilis subsp. subtilis KCTC 3135T. The near-complete genome sequences reported here represent a possible source of ribosomally synthesized, posttranslationally modified peptides, such as lantipeptides, bacteriocins, linaridin, and a lasso peptide.
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Article title: Complete genome sequence of Rhizobium sp. 11515TR isolated tomato rhizosphere from the Philippines
Authors: Andrew D Montecillo, Asuncion K. Raymundo, Irene A. Papa, Genevieve Mae B. Aquino, Albert Remus R. Rosana
Publication title: Microbiology Resource Announcements 7(7): e00903-18, 2018

Rhizobium sp. strain 11515TR was isolated from the rhizosphere of tomato in Laguna, Philippines. The 7.07-Mb complete genome comprises three replicons, one chromosome, and two plasmids, with a G+C content of 59.4% and 6,720 protein-coding genes. The genome encodes gene clusters supporting rhizosphere processes, plant symbiosis, and secondary bioactive metabolites.
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Article title: Complete genome sequence of Lactobacillus plantarum subsp. plantarum LB1-2 isolated from the hindgut of European honeybees Apis mellifera L. from the Philippines.
Authors: M Fatima C. Ilagan-Cruzada, Albert Remus R. Rosana, Andrew D. Montecillo, Noel G Sabino, Ida F. Dalmacio
Publication title: Genome announcements 6(14): e00209-18, April 2018

Lactobacillus plantarum subsp. plantarum strain LB1-2, isolated from the hindgut of European honeybees in the Philippines, is active against Paenibacillus larvae and has broad activity against several Gram-positive and Gram-negative bacteria. The complete genome sequence reported herein contains gene clusters for multiple bacteriocins and extensive gene inventories for carbohydrate metabolism.
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Article title: Draft genome sequence of Bacillus paralicheniformis F47 isolated from Algerian salty lake.
Authors: Mohamed Seghir Daas, Albert Remus R. Rosana, Jeella Z. Acedo, Malika Douzane, Farida Nateche, Salima Kebbouche-Gana, John C. Vederas
Publication title: Genome announcements 6(13): e00190-18, March 2018

Bacillus paralicheniformis F47 was isolated from a salty lake in Ain Baida-Ouargla, southern Algeria. The genome contains genes for the production of several bioactive secondary metabolites, including the siderophore bacillibactin, the lipopeptides fengycin, surfactin, and lichenysin, the antibiotics bacitracin and kanosamine, and a putative circular bacteriocin.
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Article title: Bacillus amyloliquefaciens ssp. Plantarum F11 isolated from Algerian salty lake as a source of biosurfactants and bioactive lipopeptides.
Authors: Mohamed Seghir Daas, Jeella Z. Acedo, Albert Remus R. Rosana, Fabini D. Orata, Béla Reiz, Jing Zheng, Farida Nateche, Rebecca J. Case, Salima Kebbouche-Gana, John C. Vederas
Publication title: FEMS microbiology letters 365(1), January 2018

In this study, we identified a new Bacillus strain isolated from an Algerian salty lake that produces metabolites that are active against Gram-positive and Gram-negative bacteria, as well as fungal pathogens. The draft genome sequence of the strain is presented herein. Genome sequence analysis identified the strain to be B. amyloliquefaciens subspecies plantarum F11, and showed that the strain carries the gene clusters for the production of a number of bioactive and surface-active compounds. These include the lipopeptides surfactin and fengycin, antibacterial polyketides macrolactin and bacillaene, and a putative novel lanthipeptide, among others. Through an activity-guided purification method using hydrophobic interaction chromatographic techniques, we confirmed the ability of the strain to produce fengycin lipopeptides. The identities of the isolated fengycin homologs were ascertained through tandem mass spectrometry.
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Article title: Draft genome sequences of Bacillus cereus E41 and Bacillus anthracis F34 isolated from Algerian Salt Lakes
Authors: Mohamed Seghir Daas, Albert Remus R. Rosana, Jeella Z. Acedo, Farida Nateche, Salima Kebbouche-Gana, John C. Vederas, Rebecca J. Case
Publication title: Genome Announcements 5(20): e00383-17, 2017

Two strains of Bacillus, B. cereus E41 and B. anthracis F34, were isolated from a salt lake in Aïn M’lila-Oum El Bouaghi, eastern Algeria, and Ain Baida-Ouargla, southern Algeria, respectively. Their genomes display genes for the production of several bioactive secondary metabolites, including polyhydroxyalkanoate, iron siderophores, lipopeptides, and bacteriocins.
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Article title: Cyanobacterial RNA helicase CrhR localizes to the thylakoid membrane region and co-sediments with degradosome and polysome complexes in Synechocystis sp. strain PCC 6803.
Authors: Albert Remus R. Rosana, Denise S. Whitford, Richard P. Fahlman, George W. Owttrim
Publication title: Journal of Bacteriology 198(15): 2089-2099, 2016

The cyanobacterium Synechocystis sp. strain PCC 6803 encodes a single DEAD box RNA helicase, CrhR, whose expression is tightly autoregulated in response to cold stress. Subcellular localization and proteomic analysis results indicate that CrhR localizes to both the cytoplasmic and thylakoid membrane regions and cosediments with polysome and RNA degradosome components. Evidence is presented that either functional RNA helicase activity or a C-terminal localization signal was required for polysome but not thylakoid membrane localization. Polysome fractionation and runoff translation analysis results indicate that CrhR associates with actively translating polysomes. The data implicate a role for CrhR in translation or RNA degradation in the thylakoid region related to thylakoid biogenesis or stability, a role that is enhanced at low temperature. Furthermore, CrhR cosedimentation with polysome and RNA degradosome complexes links alteration of RNA secondary structure with a potential translation-RNA degradation complex in Synechocystis.
Full text available upon request to the author

Article title: Draft Genome Sequences of Seven Bacterial Strains Isolated from a Polymicrobial Culture of Coccolith-Bearing (C-Type) Emiliania huxleyi M217
Authors: Albert Remus R. Rosana, Fabini D. Orata, Yue Xu, Danielle N. Simkus, Anna R. Bramucci, Yan Boucher, Rebecca J. Case
Publication title: Genome Announcements 4(4): e00673, July 2016

Strains of Rhodobacteraceae, Sphingomonadales, Alteromonadales, and Bacteroidetes were isolated from a polymicrobial culture of the coccolith-forming (C-type) haptophyte Emiliania huxleyi strain M217. The genomes encode genes for the production of algal growth factors and the consumption of their hosts' metabolic by-products, suggesting that the polymicrobial culture harbors many symbiotic interactions.
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Article title: Draft Genome Sequences of Four Bacterial Strains Isolated from a Polymicrobial Culture of Naked (N-Type) Emiliania huxleyi CCMP1516
Authors: Fabini D. Orata, Albert Remus R. Rosana, Yue Xu, Danielle N. Simkus, Anna R. Bramucci, Yan Boucher, Rebecca J. Case
Publication title: Genome Announcements 4(4): e00674-16

Strains of Sulfitobacter spp., Erythrobacter sp., and Marinobacter sp. were isolated from a polymicrobial culture of the naked (N-type) haptophyte Emiliania huxleyi strain CCMP1516. The genomes encode genes for the production of phytohormones, vitamins, and the consumption of their hosts' metabolic by-products, suggesting symbiotic interactions within this polymicrobial culture.
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Article title: Diverse electron sources support denitrification under hypoxia in the obligate methanotroph Methylomicrobium album strain BG8.
Authors: K. Dimitri Kits, Dustin J. Campbell, Albert R. Rosana, and Lisa Y. Stein
Publication title: Frontiers in microbiology 6: 1-11, 2016

Aerobic methane-oxidizing bacteria (MOB) are a diverse group of microorganisms that are ubiquitous in natural environments. Along with anaerobic MOB and archaea, aerobic methanotrophs are critical for attenuating emission of methane to the atmosphere. Clearly, nitrogen availability in the form of ammonium and nitrite have strong effects on methanotrophic activity and their natural community structures. Previous findings show that nitrite amendment inhibits the activity of some cultivated methanotrophs; however, the physiological pathways that allow some strains to transform nitrite, expression of gene inventories, as well as the electron sources that support this activity remain largely uncharacterized. Here we show that Methylomicrobium album strain BG8 utilizes methane, methanol, formaldehyde, formate, ethane, ethanol, and ammonia to support denitrification activity under hypoxia only in the presence of nitrite. We also demonstrate that transcript abundance of putative denitrification genes, nirS and one of two norB genes, increased in response to nitrite. Furthermore, we found that transcript abundance of pxmA, encoding the alpha subunit of a putative copper-containing monooxygenase, increased in response to both nitrite and hypoxia. Our results suggest that expression of denitrification genes, found widely within genomes of aerobic methanotrophs, allow the coupling of substrate oxidation to the reduction of nitrogen oxide terminal electron acceptors under oxygen limitation. The present study expands current knowledge of the metabolic flexibility of methanotrophs by revealing that a diverse array of electron donors support nitrite reduction to nitrous oxide under hypoxia.
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Article title: Autoregulation of RNA helicase expression in response to temperature stress in Synechocystis sp. PCC 6803.
Authors: Albert Remus R. Rosana,Danuta Chamot,George W. Owttrim
Publication title: PloS ONE 7: e48683, 2012

RNA helicases are ubiquitous enzymes whose modification of RNA secondary structure is known to regulate RNA function. The pathways controlling RNA helicase expression, however, have not been well characterized. Expression of the cyanobacterial RNA helicase, crhR, is regulated in response to environmental signals that alter the redox poise of the electron transport chain, including light and temperature. Here we analyze crhR expression in response to alteration of abiotic conditions in wild type and a crhR mutant, providing evidence that CrhR autoregulates its own expression through a combination of transcriptional and post-transcriptional mechanisms. Temperature regulates crhR expression through alteration of both transcript and protein half-life which are significantly extended at low temperature (20°C). CrhR-dependent mechanisms regulate both the transient accumulation of crhR transcript at 20°C and stability of the CrhR protein at all temperatures. CrhR-independent mechanisms regulate temperature sensing and induction of crhR transcript accumulation at 20°C and the temperature regulation of crhR transcript stability, suggesting CrhR is not directly associated with crhR mRNA turnover. Many of the processes are CrhR- and temperature-dependent and occur in the absence of a correlation between crhR transcript and protein abundance. The data provide important insights into not only how RNA helicase gene expression is regulated but also the role that rearrangement of RNA secondary structure performs in the molecular response to temperature stress. We propose that the crhR-regulatory pathway exhibits characteristics similar to the heat shock response rather than a cold stress-specific mechanism.
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Article title: Inactivation of a Low Temperature-Induced RNA Helicase in Synechocystis sp. PCC 6803: Physiological and Morphological Consequences
Authors: Albert Remus R. Rosana, Meghana Ventakesh, Danuta Chamot, Laura M. Patterson-Fortin, Oxana Tarassova, George S. Espie, George W. Owttrim
Publication title: Plant and Cell Physiology 53(4): 646-658, April 2012

Inactivation of the DEAD box RNA helicase, crhR, has dramatic effects on the physiology and morphology of the photosynthetic cyanobacterium, Synechocystis sp. PCC 6803. These effects are observed at both normal growth temperature (30°C) and under cold stress (20°C), indicating that CrhR performs crucial function(s) at all temperatures. A major physiological effect is the rapid cessation of photosynthesis upon temperature downshift from 30 to 20°C. This defect does not originate from an inability to transport or accumulate inorganic carbon or a deficiency in photosynthetic capacity as the mutant has sufficient electron transport and enzymatic capacity to sustain photosynthesis at 30°C and inorganic carbon (Ci) accumulation at 20°C. Oxygen consumption in the presence of methyl viologen indicated that while electron transport capacity is sufficient to accumulate Ci, the mutant does not possess sufficient activity to sustain carbon fixation at maximal rates. These defects are correlated with severely impaired cell growth and decreased viability, cell size and DNA content at low temperature. The ΔcrhR mutant also progressively accumulates structural abnormalities at low temperature that cannot be attributed solely to reactive oxygen species (ROS)-induced photooxidative damage, suggesting that they are manifestations of pre-existing defects that are amplified over time. The data indicate that the observed physiological and morphological effects are intimately related to crhR mutation, implying that the lack of CrhR RNA unwinding/annealing activity results in the inability to execute one or more vital steps in photosynthesis that are required at all temperatures but are crucial at low temperature.
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  • Gawad Pedro 2022 -- Outstanding Alumnus, Pedro Guevara Memorial National High School, Santa Cruz Laguna
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  • Alexander Graham Bell Scholarship (2017-2020, declined in lieu of Vanier)
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  • MSc Graduate Teaching Assistantship (2010-2013)
  • Magna cum laude (2005)
  • Valedictorian (2002)


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