Isolation of antibacterial polypeptide from Aspergillus Niger LC3 isolate

Bacteria, fungi, viruses and parasites developed or have developed resistance to the most potent antibiotics available used. Parallel to this, increases in against antimicrobial drug resistant infections are now reported. Therefore, the discovery of new antimicrobial agents has become compulsory and at the same time a situation that should be continuous. As antimicrobial agents; secondary metabolites of various microorganisms and organic extracts of some plants come to the fore. However, in the last decade, researchers have been in the combat against microorganisms; more specifically and more effectively focused on natural peptides (AMPs), a new antimicrobial group. In this thesis, the extracellular proteins were isolated from isolate LC3 beloning to Aspergillus and then tested for antimicrobial activity against Staphylococcus aureus (ATCC 25923) and Methicillin resistant Staphylococcus aureus (MRSA). Antimicrobial activity was determined by the trypsin / proteinase K test, which was protein-related to, and it was determined that this protein was a protein of 11 kDa by gel overlay assay. Then minimum inhibiyory concentration of purified AMP molecules against S. aureus and MRSA was 8 µg/µl and 32 µg/µl, respectively and the AMP molecule was confirmed. ITS sequence analysis showed that LC3 isolate was identified as Aspergillus niger and recorded in GenBank with access number MK332597. As a result, the purified AMP molecule has the potential to be used in infections caused by S. aureus.