Popis: |
This study aimed to investigate the antibacterial actions of glycinin basic peptide against the oxidative phosphorylation system of Aspergillus niger (A. niger). The structural disruption and lipid peroxidation of the A. niger membrane were assessed via changes in 1,6-diphenyl-1,3,5-hexatriene fluorescence intensity and malondialdehyde content. Glycinin basic peptide decreased the fluorescence intensity of 1,6-diphenyl-1,3,5-hexatriene and increased the malondialdehyde content in A. niger cells. These results indicated that glycinin basic peptide disrupted the structural and functional integrity of the A. niger membrane and triggered severe lipid peroxidation. Moreover, the types and quantities of A. niger proteins decreased after exposure to glycinin basic peptides, as determined by protein electrophoresis. The activities of five key enzymes in the A. niger oxidative phosphorylation system were significantly inhibited after exposure to glycinin basic peptide. As observed by fluorescence quantitative polymerase chain reaction, glycinin basic peptide could significantly downregulate genes related to these enzymes (expression level of these genes decreased more than 50% when glycinin basic peptide reached 3.00 mg/mL). The inactivation of key enzymes and downregulation of corresponding genes indicated that glycinin basic peptide disrupted oxidative phosphorylation system, resulting in cell death of A. niger. |