Screening, Characterization and Optimization of antibacterial peptides, produced byBacillus safensisstrain MK-12 isolated from waste dump soil KP, Pakistan

Abstract

Aims:The 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. Methods and results:The 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 0 C in shaking incubator when fermented in optimized medium. Conclusion:The 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.Significance and impact: This 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.

A Metagenomic Nanopore Sequence Analysis Combined with Conventional Screening and Spectroscopic Methods for Deciphering the Antimicrobial Metabolites Produced by Alcaligenes faecalis Soil Isolate MZ921504

“…The antimicrobial resistance patterns of the respective clinical isolates are displayed in Table 4 . The 17 isolates were inoculated on Mueller Hinton agar (MHA) and the test organisms were inoculated perpendicularly to the isolate [ 42 , 43 ]. The plates were then incubated for 24 h. at 37 °C.…”

Isolation, Identification and Screening of Bacillus species with Antimicrobial Activity from Different Soil Samples of Kathmandu Valley

“…(standardized with 0.5 McFarland, with cell suspension 108 CFU/ml) were then streaked perpendicular to the line of growth of isolate. These plates were then incubated overnight at 37˚C .The zone of inhibition was measured respectively after the complete incubation [10].…”