Enhanced adherence to and invasion of PUVEC and PK-15 cells due to the overexpression of RfaD, ThyA and Mip in the ΔompP2 mutant of Haemophilus parasuis SC096 strain.
In Gram-negative bacteria, porins not only contribute to bacterial homeostasis, but also are involved in adherence to and invasion of host cells. Haemophilus parasuis outer membrane protein P2 (OmpP2), a member of the porin family, is an important surface protein involved in serum resistance. To further determine the features of OmpP2, the ability of ompP2 deficient mutant (ΔompP2) of a H. parasuis SC096 strain to interact with porcine umbilicus veins endothelial cells (PUVEC) and porcine kidney epithelial cells (PK-15) was evaluated in this study. The ΔompP2 mutant exhibited dramatically increased ability to adhere to and invade PUVEC and PK-15 cells. Conversely, pretreatment of cell lines with purified native OmpP2 porins significantly inhibited adhesion and invasion of the SC096 strain to the both host cells. To explain the unexpected phenomenon, a 2-dimensional gel electrophoresis-based proteomics comparison was performed between the wild-type SC096 and ΔompP2 mutant strains. There were 55 differentially expressed proteins identified from mutant. Among them, three overexpressed proteins of the ADP-l-glycero-d-mannoheptose-6-epimerase RfaD, thymidylate synthase ThyA and putative macrophage infectivity potentiator-related protein Mip were confirmed as molecular targets that modulated adherence and invasion capacities of the ΔompP2 mutant. Collectively, the OmpP2 of the H. parasuis SC096 strain mediated the adherence to and invasion of cells and loss of OmpP2 expression resulted in promoted cell-adherence and invasion properties which were due to the overexpression of RfaD, ThyA and Mip.
Key Laboratory of Animal Vaccine Development, Ministry of Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, People's Republic of China; College of Life Science and Technology, Southwest University for Nationalities, Chengdu 610041, People's Republic of China.
Bin
B
Zhang
Key Laboratory of Animal Vaccine Development, Ministry of Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, People's Republic of China.
Chenggang
C
Xu
Key Laboratory of Animal Vaccine Development, Ministry of Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, People's Republic of China.
Lingyun
L
Zhang
Key Laboratory of Animal Vaccine Development, Ministry of Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, People's Republic of China.
Suming
S
Zhou
Key Laboratory of Animal Vaccine Development, Ministry of Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, People's Republic of China.
Saixiang
S
Feng
Key Laboratory of Animal Vaccine Development, Ministry of Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, People's Republic of China.
Yanbin
Y
He
Key Laboratory of Animal Vaccine Development, Ministry of Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, People's Republic of China. Electronic address: mliao@scau.edu.cn.
Ming
M
Liao
D000818:Animals; D001422:Bacterial Adhesion / Q000502:physiology; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D001426:Bacterial Proteins / Q000096:biosynthesis*; D002238:Carbohydrate Epimerases / Q000096:biosynthesis*; D002460:Cell Line; D015180:Electrophoresis, Gel, Two-Dimensional; D042783:Endothelial Cells / Q000382:microbiology; D004847:Epithelial Cells / Q000382:microbiology; D044137:Haemophilus parasuis / Q000201:enzymology / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D019696:Peptidylprolyl Isomerase / Q000096:biosynthesis*; D013552:Swine; D013940:Thymidylate Synthase / Q000096:biosynthesis*
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; C063931:Omp2 protein, bacteria; D013940:Thymidylate Synthase; C037213:ADP-L-glycero-D-mannoheptose-6-epimerase; D002238:Carbohydrate Epimerases; D019696:Peptidylprolyl Isomerase