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bioRxiv · 10.1101/308205

Screening, Characterization and Optimization of antibacterial peptides, produced by Bacillus safensis strain MK-12 isolated from waste dump soil KP, Pakistan

Iqbal, S.·Qasim, M.·begum, F.·Rahman, H.·Sajid, I.
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Abstract

AimsThe current study was designed to isolate, screen and identify the indigenous soil antibacterial exhibiting bacteria (AEB) and effect of various parameters on growth of AEB and antibacterial peptides production.\n\nMethods and resultsThe soil isolates were screened for antagonistic activity against a set of ATCC and local MDR human pathogenic bacterial strains. The antibacterial compound was protein in nature, exhibited no haemolysis and molecular weight was less than 20 KDa. The potential AEB isolate was identified by morphology, biochemical testing and by 16S rRNA gene sequencing as B. safensis MK-12. Growth and antibacterial activity was optimized for B. safensis strain MK-12, exhibited maximum growth as well as antibacterial activity after 48 hours of incubation at pH 8, 30 {degrees}C in shaking incubator when fermented in optimized medium.\n\nConclusionThe current study results indicate that indigenous soil is rich source of AEB and could be a promising source of antimicrobial compounds to fight against MDR bacteria in future.\n\nSignificance and impactThis is the first scientific report on soil bacteria from northern region of Pakistan as per our knowledge. Therefore, screening of soil bacteria for antibacterial activity from unexplored area may contribute towards new antibiotic. Selected soil strain in the current study exhibited promising antibacterial activity against human pathogenic MDR bacterial strains.

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Iqbal, S., Qasim, M., begum, F., Rahman, H., Sajid, I.. 2018-04-25. Screening, Characterization and Optimization of antibacterial peptides, produced by Bacillus safensis strain MK-12 isolated from waste dump soil KP, Pakistan. https://doi.org/10.1101/308205

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