Truncated type IV pilin PilA(108) activates the intramembrane protease AlgW to cleave MucA and PilA(108) itself in vitro.
For alginate production in Pseudomonas aeruginosa, the intramembrane protease AlgW must be activated to cleave the periplasmic domain of anti-sigma factor MucA for release of the sequestered ECF sigma factor AlgU. Previously, we reported that three tandem point mutations in the pilA gene, resulting in a truncated type IV pilin termed PilA(108) with a C-terminal motif of phenylalanine-threonine-phenylalanine (FTF), induced mucoidy in strain PAO579. In this study, we purified PilA(108) protein and synthesized a peptide 'SGAGDITFTF' corresponding to C-terminus of PilA(108) and found they both caused the degradation of MucA by AlgW. Interestingly, AlgW could also cleave PilA(108) between alanine(62) and glycine(63) residues. Overexpression of the recombinant FTF motif-bearing MucE protein, originally a small periplasmic polypeptide with the C-terminal motif WVF, could induce mucoid conversion in the PAO1 strain. In all, our results provided a model of activation of AlgW by another protein ending with proper motifs. Our data suggest that in addition to MucA cleavage, AlgW may cleave other substrates.
Institute of Hydrobiology, Chinese Academy of Sciences, 7 South Donghu Road, Wuchang District, Wuhan, 430072, China.|Guizhou Provincial People's Hospital, Guiyang, 550002, Guizhou, China.
Ronghui
R
Li
Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine at Marshall University, Huntington, WV, USA.
Ryan T
RT
Withers
Institute of Hydrobiology, Chinese Academy of Sciences, 7 South Donghu Road, Wuchang District, Wuhan, 430072, China.|University of Chinese Academy of Sciences, Beijing, 100049, China.
Jingcheng
J
Dai
Institute of Hydrobiology, Chinese Academy of Sciences, 7 South Donghu Road, Wuchang District, Wuhan, 430072, China.
Jing
J
Ruan
Guizhou Provincial People's Hospital, Guiyang, 550002, Guizhou, China.
Wei
W
Li
School of Life Sciences and Technology, Hubei Engineering University, Xiaogan, 432000, China.
Yujun
Y
Dai
Institute of Hydrobiology, Chinese Academy of Sciences, 7 South Donghu Road, Wuchang District, Wuhan, 430072, China.|University of Chinese Academy of Sciences, Beijing, 100049, China.
Weixing
W
An
Institute of Hydrobiology, Chinese Academy of Sciences, 7 South Donghu Road, Wuchang District, Wuhan, 430072, China.|University of Chinese Academy of Sciences, Beijing, 100049, China.
Dianzhen
D
Yu
Institute of Hydrobiology, Chinese Academy of Sciences, 7 South Donghu Road, Wuchang District, Wuhan, 430072, China.|University of Chinese Academy of Sciences, Beijing, 100049, China.
Hehong
H
Wei
Institute of Hydrobiology, Chinese Academy of Sciences, 7 South Donghu Road, Wuchang District, Wuhan, 430072, China.|University of Chinese Academy of Sciences, Beijing, 100049, China.
Ming
M
Xia
School of Life Sciences and Technology, Hubei Engineering University, Xiaogan, 432000, China.
Chunyuan
C
Tian
Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine at Marshall University, Huntington, WV, USA.
Hongwei D
HD
Yu
Institute of Hydrobiology, Chinese Academy of Sciences, 7 South Donghu Road, Wuchang District, Wuhan, 430072, China. qiu@ihb.ac.cn.|University of Chinese Academy of Sciences, Beijing, 100049, China. qiu@ihb.ac.cn.|School of Life Sciences and Technology, Hubei Engineering University, Xiaogan, 432000, China. qiu@ihb.ac.cn.
Dongru
D
Qiu
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D036781:Fimbriae Proteins / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D010447:Peptide Hydrolases / Q000235:genetics / Q000378:metabolism*; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000378:metabolism*; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D012808:Sigma Factor / Q000378:metabolism
C097646:AlgW protein, Pseudomonas aeruginosa; D001426:Bacterial Proteins; C063757:MucA protein, Bacteria; D012097:Repressor Proteins; D012808:Sigma Factor; D036781:Fimbriae Proteins; D010447:Peptide Hydrolases
AlgW; Mucoid conversion; Pseudomonas aeruginosa; Truncated type IV pilin