Antibacterial and membrane-damaging activities of mannosylated bovine serum albumin.
The aim of this study was to test whether mannosylated BSA (Man-BSA) exerts antibacterial activity on Escherichia coli (gram-negative bacteria) and Staphylococcus aureus (gram-positive bacteria) via its membrane-damaging effect. Man-BSA caused inhibition of growth of E. coli and S. aureus. Moreover, bactericidal action of Man-BSA on E. coli and S. aureus positively correlated with the increase in membrane permeability of the bacterial cells. Morphological examination showed that Man-BSA disrupted bacterial membrane integrity. Destabilization of the lipopolysaccharide (LPS) layer and inhibition of lipoteichoic acid (LTA) biosynthesis in the cell wall increased the bactericidal effect of Man-BSA on E. coli and S. aureus. Man-BSA also induced leakage and fusion of membrane-mimicking liposomes in E. coli and S. aureus. Man-BSA showed similar binding affinity for LPS and LTA. LPS and LTA strongly suppressed the membrane-damaging activity of Man-BSA, whereas an increase in the Man-BSA concentration attenuated the inhibitory action of LPS and LTA. Taken together, our data indicate that Man-BSA's bactericidal activity depends strongly on its ability to induce membrane permeability. Moreover, the bactericidal action of Man-BSA proven in this study suggests that Man-BSA may serve as a prototype for the development of anti-infective agents targeting E. coli and S. aureus.
Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan.
Chia-Yu
CY
Tsai
Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan.
Ying-Jung
YJ
Chen
Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
Yaw-Syan
YS
Fu
Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan; Department of Biotechnology, Kaohsiung Medical University, Kaohsiung 807, Taiwan. Electronic address: lschang@mail.nsysu.edu.tw.
Long-Sen
LS
Chang
D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002463:Cell Membrane Permeability; D002473:Cell Wall / Q000187:drug effects / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology; D008358:Mannose / Q000494:pharmacology*; D012709:Serum Albumin / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects; D013682:Teichoic Acids / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D000900:Anti-Bacterial Agents; D008070:Lipopolysaccharides; D012709:Serum Albumin; D013682:Teichoic Acids; D014409:Tumor Necrosis Factor-alpha; C023840:mannose-bovine serum albumin conjugate; C009900:lipoteichoic acid; D008358:Mannose
Bactericidal effect; Fusogenicity; Mannosylated BSA; Membrane-damaging activity