Arendt_2013_J.Biol.Chem_288_24717

Reference

Title : Identification and characterization of a periplasmic aminoacyl-phosphatidylglycerol hydrolase responsible for Pseudomonas aeruginosa lipid homeostasis - Arendt_2013_J.Biol.Chem_288_24717
Author(s) : Arendt W , Groenewold MK , Hebecker S , Dickschat JS , Moser J
Ref : Journal of Biological Chemistry , 288 :24717 , 2013
Abstract :

Specific aminoacylation of the phospholipid phosphatidylglycerol (PG) with alanine (or with lysine) was shown to render various organisms less susceptible to antimicrobial agents and environmental stresses. In this study, we make use of the opportunistic pathogen Pseudomonas aeruginosa to decode ORF PA0919-dependent lipid homeostasis. Analysis of the polar lipid content of the deletion mutant deltaPA0919 indicated significantly enlarged levels of alanyl-PG. The resulting phenotype manifested an increased susceptibility to several antimicrobial compounds when compared with the wild type. A pH-dependent PA0919 promoter located within the upstream gene PA0920 was identified. Localization experiments demonstrated that the PA0919 protein is anchored to the periplasmic surface of the inner bacterial membrane. The recombinant overproduction of wild type and several site-directed mutant proteins in the periplasm of Escherichia coli facilitated a detailed in vitro analysis of the enzymatic PA0919 function. A series of artificial substrates (p-nitrophenyl esters of various amino acids/aliphatic acids) indicated enzymatic hydrolysis of the alanine, glycine, or lysine moiety of the respective ester substrates. Our final in vitro activity assay in the presence of radioactively labeled alanyl-PG then revealed hydrolysis of the aminoacyl linkage, resulting in the formation of alanine and PG. Consequently, PA0919 was termed alanyl-PG hydrolase. The elucidated enzymatic activity implies a new regulatory circuit for the appropriate tuning of cellular alanyl-PG concentrations.

PubMedSearch : Arendt_2013_J.Biol.Chem_288_24717
PubMedID: 23792962
Gene_locus related to this paper: pseae-q9i538

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Citations formats

Arendt W, Groenewold MK, Hebecker S, Dickschat JS, Moser J (2013)
Identification and characterization of a periplasmic aminoacyl-phosphatidylglycerol hydrolase responsible for Pseudomonas aeruginosa lipid homeostasis
Journal of Biological Chemistry 288 :24717

Arendt W, Groenewold MK, Hebecker S, Dickschat JS, Moser J (2013)
Journal of Biological Chemistry 288 :24717