Acinetobacter strains carry two functional oligosaccharyltransferases, one devoted exclusively to type IV pilin, and the other one dedicated to O‐glycosylation of multiple proteins. Issue 5 (6th April 2015)

• Record Type: Journal Article
• Authors: Harding, Christian M.; Nasr, Mohamed A.; Kinsella, Rachel L.; Scott, Nichollas E.; Foster, Leonard J.; Weber, Brent S.; Fiester, Steve E.; Actis, Luis A.; Tracy, Erin N.; Munson, Robert S.; Feldman, Mario F.
• Is Part Of: Molecular microbiology. Volume 96:Issue 5(2015)
• Page Start: 1023
• Page End: 1041
• Publication Date: 2015-04-06
• Subjects: Molecular microbiology -- Periodicals; 572.829
• DOI: 10.1111/mmi.12986
• Languages: English
• ISSNs: 0950-382X

Abstract

<abstract abstract-type="main"> <title>Summary</title> <p>Multiple species within the <italic>A</italic><italic>cinetobacter</italic> genus are nosocomial opportunistic pathogens of increasing relevance worldwide. Among the virulence factors utilized by these bacteria are the type IV pili and a protein <italic>O</italic>‐glycosylation system. Glycosylation is mediated by <italic>O</italic>‐oligosaccharyltransferases (<italic>O</italic>‐OTases), enzymes that transfer the glycan from a lipid carrier to target proteins. <italic>O</italic>‐oligosaccharyltransferases are difficult to identify due to similarities with the WaaL ligases that catalyze the last step in lipopolysaccharide synthesis. A bioinformatics analysis revealed the presence of two genes encoding putative <italic>O</italic>‐OTases or WaaL ligases in most of the strains within the genus <italic>A</italic><italic>cinetobacter</italic>. Employing <italic>A</italic><italic>. nosocomialis</italic> M2 and <italic>A</italic><italic>. baylyi</italic> ADP1 as model systems, we show that these genes encode two <italic>O</italic>‐OTases, one devoted uniquely to type IV pilin, and the other one responsible for glycosylation of multiple proteins. With the exception of ADP1, the pilin‐specific OTases in <italic>Acinetobacter</italic> resemble the TfpO/PilO <italic>O</italic>‐OTase from <italic>P</italic><italic>seudomonas aeruginosa</italic>. In ADP1 instead, the two <italic>O</italic>‐OTases are closely related to PglL, the general <italic>O</italic>‐OTase first discovered in <italic>N</italic><italic>eisseria</italic>. However, one of them is exclusively dedicated to the glycosylation of the pilin‐like protein ComP. Our data reveal an intricate and remarkable evolutionary pathway for bacterial <italic>O</italic>‐OTases and provide novel tools for glycoengineering.</p> </abstract>