Bacillus spp with an Antibacterial Activity

Abstract

Bacterial resistance to antibiotics poses a serious challenge to chemotherapy. Indeed, in recent decades, the risk of contracting infectious diseases has increased significantly due to the emergence and spread of multi-drug-resistant bacteria. The whole world is thus confronted with this situation which motivated scientists to find out new active molecules with an antibacterial effect. Therefore, the present investigation aims to isolate and identify microorganisms secreting substances with an antibacterial activity and to partially characterize their extracts. Thus, six bacteria were isolated from soil and water of different biotopes of Fez Morocco having an antibacterial effect against M. smegmatis, M. aurum, Gram-positive and Gram-negative bacteria. Based on biochemical characterization and 16S rDNA sequence analysis, it was revealed that the isolates belong to the genus Bacillus. The antibacterial activity of three of them was fully affected by proteases (pepsin and proteinase K) and heat treatment at 80C and 100C but it was stable at 4C for a month and 37C during 3h. The lost of the activity suggests a proteinaceous nature of the bio-active compounds, which might be useful in the development of antibacterial agents after their total purification in further work against bacterial infections.