In Situ Cultured Bacterial Diversity from Iron Curtain Cave, Chilliwack, British Columbia, Canada

Abstract

Abstract:The culturable bacterial diversity from Iron Curtain Cave, Chilliwack, British Columbia, Canada was examined. Sixty five bacterial isolates were successfully cultivated, purified, and identified based on 16S rRNA gene sequencing. Four distinguishable phyla, i.e., Actinobacteria (44.61%), Proteobacteria (27.69%), Firmicutes (20%) and Bacteroidetes (7.69%) were identified. Arthrobacter (21.53%) was identified as the major genus, followed by Sporosarcina (9.23%), Stenotrophomonas (9.23%), Streptomyces (6.15%), Brevundimonas (4.61%), and Crocebacterium (2.8%). Noteworthy, 12.3% of the population was recognized as unidentified bacteria. The isolates were evaluated for their potential antimicrobial activities against multidrug resistant microbial strains. Two species of the genus Streptomyces exhibited a wide range of antimicrobial activities against multidrug resistance (MDR) strains of Escherichia coli and Pseudomonas spp. along with non-resistant strains of Staphylococcus aureus and E. coli. However, all of the antimicrobial activities were only observed when the isolates were grown at 8 • C in different media. To the best of our knowledge, this is the first study conducted on the Iron Curtain Cave's bacterial diversity, and reveals some bacterial isolates that have never been reported from a cave. Bacterial isolates identified with antimicrobial properties demonstrated that the Iron Curtain Cave can be further considered as a potential habitat for antimicrobial agents.

Culture dependent analysis of bacterial diversity in Canada’s Raspberry Rising Cave revealed antimicrobial properties

“…Genomic DNA (gDNA) extraction from the bacterial isolates were performed as per previous studies (Hoffman & Winston, 1987;Ghosh et al, 2017). Following the extraction, the gDNA was subjected to polymerized chain reaction amplification of the 16S rRNA gene as described previously (Ghosh et al, 2017). The 27F (5'-AGAGTTTGATCMTGGCTCAG-3') and 1492R (5'-TACGGYTACCTTGTTACGACTT-3') primers were used for the amplification reaction.…”

“…The MDR E. coli (New Delhi strain) #15-318, E. coli #15-102 and methicillin-resistant Staphylococcus aureus (MRSA)-43300 while the regular non-resistant strains E. coli-33 and S. aureus were chosen. All the test strains used were procured from our previous studies (Ghosh et al, 2017;Ghosh et al, 2018). The bacterial strains were inoculated in 3 mL of the nutrient broth (Criterion™Dehydrated CultureMedia, Hardy Diagnostics, CA, USA) and incubated overnight on a shaking test tube rotator overnight at 37°C.…”

“…The broad diversity of microorganisms within caves encompass members among Proteobacteria, Firmicutes and Actinobacteria International Journal of Speleology, 49 (1), 43-53. Tampa, FL (USA) January 2020 (Barton & Jurado, 2007;Cheeptham et al, 2013;Ghosh et al, 2016Ghosh et al, , 2017De Mandal et al, 2017). In particular, cave sediments house interesting microbial communities that include species of Streptomyces, Arthrobacter, Leifsonia, Rhodococcus, Bacillus, Paenosporosarcina, Paenibacillus, Pseudomonas, Williamsia, Leifsonia, Nocardia, Devosia (Ghosh et al, 2016;, and interactions due to the unique conditions of the cave environment (Barron et al, 2010).…”

“…The need for discovery of new antibiotics is on the rise, since pathogens continuously becoming resistant to antibiotics, and those currently available either not having specific inhibitory activities or pose concerned side effects (Cheeptham et al, 2013;Ghosh et al, 2016). In terms of the cave microbiome, a number of studies have been explored for its diversity and has exhibited a wide range of antimicrobial properties (Cheeptham, et al, 2013;Ghosh et al, 2017;Gosse et al, 2019). For instance, in a recent study from Iron Curtain Cave, Canada, two bacterial isolates were identified ICC1 and ICC4, that exhibited antagonistic properties against the multidrug resistant E. coli strains (Ghosh et al, 2017).…”

“…In terms of the cave microbiome, a number of studies have been explored for its diversity and has exhibited a wide range of antimicrobial properties (Cheeptham, et al, 2013;Ghosh et al, 2017;Gosse et al, 2019). For instance, in a recent study from Iron Curtain Cave, Canada, two bacterial isolates were identified ICC1 and ICC4, that exhibited antagonistic properties against the multidrug resistant E. coli strains (Ghosh et al, 2017). Further genomic and metabolome analysis revealed that though the isolates are highly homologous with the terrestrial bacteria Streptomyces lavendulae but there were not the same, and possess expanded metabolic potentials (Gosse et al, 2019).…”