الفهرس | Only 14 pages are availabe for public view |
Abstract One antimicrobial peptide was isolated and purified to 5.5-fold purification from the crude lysate of immunized Aedes caspius larvae by (NH4) 2SO4 fractionation, ion-exchange chromatography, and reverse-phase high performance liquid chromatography (HPLC). The peptide, named ACAm, was found to be heat stable below 80{u00B0}C and attained the maximum antimicrobial activities at acidic pH range. The estimated molecular weight of ACAm by sodium dodecyl sulphate polyacrylamide gel (SDS-PAGE), under non-reducing conditions, was 4 KDa. Using isoelectric focusing (IEF), ACAm exhibited pI in basic pH (8.4) belonging to cationic peptides. The hydrophobic amino acids represented 45.7% of the peptide where the calculated hydrophobicity indexwas 1.12. Both the crude extract and ACAm exhibited strong antimicrobial activities against gram- positive and Gram-negative bacteria as well as against peptidoglycans and lipopolysacchrides of bacterial cell walls |