Premium
Integration of chemotaxis, transport and catabolism in P seudomonas putida and identification of the aromatic acid chemoreceptor PcaY
Author(s) -
Luu Rita A.,
Kootstra Joshua D.,
Nesteryuk Vasyl,
Brunton Ceanne N.,
Parales Juanito V.,
Ditty Jayna L.,
Parales Rebecca E.
Publication year - 2015
Publication title -
molecular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 247
eISSN - 1365-2958
pISSN - 0950-382X
DOI - 10.1111/mmi.12929
Subject(s) - major facilitator superfamily , permease , biology , biochemistry , chemotaxis , pseudomonas putida , catabolism , mutant , lanthionine , repressor , regulon , metabolism , amino acid , enzyme , gene , gene expression , receptor
Summary Aromatic and hydroaromatic compounds that are metabolized through the β‐ketoadipate catabolic pathway serve as chemoattractants for P seudomonas putida F 1. A screen of P . putida F 1 mutants, each lacking one of the genes encoding the 18 putative m ethyl‐accepting c hemotaxis p roteins ( MCP s), revealed that pcaY encodes the MCP required for metabolism–independent chemotaxis to vanillate, vanillin, 4‐hydroxybenzoate, benzoate, protocatechuate, quinate, shikimate, as well as 10 substituted benzoates that do not serve as growth substrates for P . putida F 1. Chemotaxis was induced during growth on aromatic compounds, and an analysis of a pcaY ‐ lacZ fusion revealed that pcaY is expressed in the presence of β‐ketoadipate, a common intermediate in the pathway. pcaY expression also required the transcriptional activator PcaR, indicating that pcaY is a member of the pca regulon, which includes three unlinked gene clusters that encode five enzymes required for the conversion of 4‐hydroxybenzoate to tricarboxylic acid cycle intermediates as well as the major facilitator superfamily transport protein PcaK. The 4‐hydroxybenzoate permease PcaK was shown to modulate the chemotactic response by facilitating the uptake of 4‐hydroxybenzoate, which leads to the accumulation of β‐ketoadipate, thereby increasing pcaY expression . The results show that chemotaxis, transport and metabolism of aromatic compounds are intimately linked in P . putida .