1. Recovery of metallo-tolerant and antibiotic resistant psychrophilic bacteria from Siachen glacier, Pakistan.
- Author
-
Rafiq M, Hayat M, Anesio AM, Jamil SUU, Hassan N, Shah AA, and Hasan F
- Subjects
- Adaptation, Physiological, Antibiosis, Bacteria classification, Bacteria genetics, Gram-Negative Bacteria classification, Gram-Negative Bacteria genetics, Gram-Negative Bacteria isolation & purification, Gram-Positive Bacteria classification, Gram-Positive Bacteria genetics, Gram-Positive Bacteria isolation & purification, Microbial Sensitivity Tests, Pakistan, RNA, Ribosomal, 16S genetics, Salt Tolerance drug effects, Sodium Chloride pharmacology, Bacteria isolation & purification, Cold Temperature, Drug Resistance, Microbial, Ice Cover microbiology, Metals, Heavy metabolism
- Abstract
Cultureable bacterial diversity of previously unexplored Siachen glacier, Pakistan, was studied. Out of 50 isolates 33 (66%) were Gram negative and 17 (34%) Gram positive. About half of the isolates were pigment producers and were able to grow at 4-37°C. 16S rRNA gene sequences revealed Gram negative bacteria dominated by Proteobacteria (especially γ-proteobacteria and β-proteobacteria) and Flavobacteria. The genus Pseudomonas (51.51%, 17) was dominant among γ- proteobacteria. β-proteobacteria constituted 4 (12.12%) Alcaligenes and 4 (12.12%) Janthinobacterium strains. Among Gram positive bacteria, phylum Actinobacteria, Rhodococcus (23.52%, 4) and Arthrobacter (23.52%, 4) were the dominating genra. Other bacteria belonged to Phylum Firmicutes with representative genus Carnobacterium (11.76%, 2) and 4 isolates represented 4 genera Bacillus, Lysinibacillus, Staphylococcus and Planomicrobium. Most of the Gram negative bacteria were moderate halophiles, while most of the Gram positives were extreme halophiles and were able to grow up to 6.12 M of NaCl. More than 2/3 of the isolates showed antimicrobial activity against multidrug resistant S. aureus, E. coli, Klebsiella pneumonia, Enterococcus faecium, Candida albicans, Aspergillus flavus and Aspergillus fumigatus and ATCC strains. Gram positive bacteria (94.11%) were more resistant to heavy metals as compared to Gram negative (78.79%) and showed maximum tolerance against iron and least tolerance against mercury.
- Published
- 2017
- Full Text
- View/download PDF