A bactericidal permeability-increasing protein (BPI) from manila clam Ruditapes philippinarum: Investigation on the antibacterial activities and antibacterial action mode

Dinglong Yang; Yijing Han; Lizhu Chen; Ruiwen Cao; Qing Wang; Zhijun Dong; Hui Liu; Xiaoli Zhang; Qianqian Zhang; Jianmin Zhao

doi:10.1016/j.fsi.2019.08.050

A bactericidal permeability-increasing protein (BPI) from manila clam Ruditapes philippinarum: Investigation on the antibacterial activities and antibacterial action mode

Fish Shellfish Immunol. 2019 Oct:93:841-850. doi: 10.1016/j.fsi.2019.08.050. Epub 2019 Aug 17.

Authors

Affiliations

¹ Muping Coastal Environment Research Station, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China; Research and Development Center for Efficient Utilization of Coastal Bioresources, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China.
² Muping Coastal Environment Research Station, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China.
³ Shandong Marine Resource and Environment Research Institute, Yantai, 264006, PR China.
⁴ Muping Coastal Environment Research Station, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China; Research and Development Center for Efficient Utilization of Coastal Bioresources, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China; Center for Ocean Mega-science, Chinese Academy of Sciences, Qingdao, 266071, PR China. Electronic address: jmzhao@yic.ac.cn.

PMID: 31430558
DOI: 10.1016/j.fsi.2019.08.050

Abstract

Bactericidal permeability-increasing protein (BPI) is an antimicrobial protein with potent endotoxin-neutralising activity and plays a crucial role in innate immunity against bacterial infection. In the present study, a bpi (designed as rpbpi) was identified and characterized from manila clam Ruditapes philippinarum. Multiple alignments and phylogenetic analysis suggested that rpbpi was a new member of the bpis family. In non-stimulated clams, rpbpi transcripts were ubiquitously expressed in all tested tissues with the highest expression level in hemocytes. After Vibrio anguillarum challenge, the expression levels of rpbpi mRNA in hemocytes were up-regulated significantly at 3 h and 48 h compared with that in the control, which were 4.01- and 19.10-fold (P < 0.05), respectively. The recombinant RpBPI (rRpBPI) showed high antibacterial activities against Gram-negative bacteria Escherichia coli and V. anguillarum, but not Staphylococcus aureus. Moreover, membrane integrity analysis revealed that rRpBPI increased the membrane permeability of Gram-negative bacteria, and then resulted in cell death. Overall, our results suggested that RpBPI played an important role in the elimination of invaded bacteria through membrane-disruptive activity.

Keywords: Antimicrobial activity; Bactericidal permeability-increasing protein; Membrane disruption; Ruditapes philippinarum.

MeSH terms

Amino Acid Sequence
Animals
Anti-Bacterial Agents / metabolism
Antimicrobial Cationic Peptides / chemistry
Antimicrobial Cationic Peptides / genetics*
Antimicrobial Cationic Peptides / immunology*
Base Sequence
Bivalvia / genetics*
Bivalvia / immunology*
Blood Proteins / chemistry
Blood Proteins / genetics*
Blood Proteins / immunology*
Gene Expression Profiling
Gene Expression Regulation / immunology*
Gram-Negative Bacteria / physiology
Immunity, Innate / genetics*
Phylogeny
Sequence Alignment

Substances

Anti-Bacterial Agents
Antimicrobial Cationic Peptides
Blood Proteins
bactericidal permeability increasing protein