1. Penicillin-binding protein folding is dependent on the PrsA peptidyl-prolyl cis-trans isomerase in Bacillus subtilis
- Author
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Oscar P. Kuipers, Bogumila C. Marciniak, Milla Pietiäinen, Marika Vitikainen, Vesa P. Kontinen, Doerte Becher, Pascal Courtin, Raili Seppala, Hanne-Leena Hyyryläinen, Kathleen Dahncke, Marie-Pierre Chapot-Chartier, and Andreas Otto
- Subjects
Penicillin binding proteins ,biology ,Isomerase ,Bacillus subtilis ,biology.organism_classification ,Microbiology ,Cell membrane ,Cell wall ,chemistry.chemical_compound ,medicine.anatomical_structure ,chemistry ,Biochemistry ,Cis-trans-Isomerases ,medicine ,Protein folding ,Peptidoglycan ,Molecular Biology - Abstract
Summary The PrsA protein is a membrane-anchored peptidyl-prolyl cis-trans isomerase in Bacillus subtilis and most other Gram-positive bacteria. It catalyses the post-translocational folding of exported proteins and is essential for normal growth of B. subtilis. We studied the mechanism behind this indispensability. We could construct a viable prsA null mutant in the presence of a high concentration of magnesium. Various changes in cell morphology in the absence of PrsA suggested that PrsA is involved in the biosynthesis of the cylindrical lateral wall. Consistently, four penicillin-binding proteins (PBP2a, PBP2b, PBP3 and PBP4) were unstable in the absence of PrsA, while muropeptide analysis revealed a 2% decrease in the peptidoglycan cross-linkage index. Misfolded PBP2a was detected in PrsA-depleted cells, indicating that PrsA is required for the folding of this PBP either directly or indirectly. Furthermore, strongly increased uniform staining of cell wall with a fluorescent vancomycin was observed in the absence of PrsA. We also demonstrated that PrsA is a dimeric or oligomeric protein which is localized at distinct spots organized in a helical pattern along the cell membrane. These results suggest that PrsA is essential for normal growth most probably as PBP folding is dependent on this PPIase.
- Published
- 2010