title: Identification of three genes encoding for the late acyltransferases of lipid A in Cronobacter sakazakii.
abstract: Lipid A, the hydrophobic anchor of lipopolysaccharide, is an essential component in the outer membrane of most Gram-negative bacteria. Food-borne pathogen  Cronobacter sakazakii synthesizes two lipid A species, differing by the length of the secondary acyl chain. In this work, we identified three genes ESA02293, ESA02951 and ESA01386 encoding for the late acyltransferases of lipid A biosynthesis pathway in  C. sakazakii. Based on the sequence alignment, proteins YP_001438378.1 encoded by ESA02293, YP_001439016.1 encoded by ESA02951, and YP_001437482.1 encoded by ESA01386 are homologous to E. coli LpxL, LpxP and LpxM, respectively. Functions of the three acyltransferases were confirmed by overexpressing the genes in E. coli, isolating lipid As and analyzing their structures using an ESI/MS. C. sakazakii LpxL and LpxM transfer a C14:0 secondary acyl chain to the 2'- and 3'-position of lipid A, respectively. C. sakazakii LpxP can transfer either a C16:1 or a C14:0 secondary acyl chains to the 2'-position of lipid A.
authors: State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China.
authors: Liping
authors: L
authors: Cai
authors: Yanyan
authors: Y
authors: Li
authors: Guanjun
authors: G
authors: Tao
authors: Wen
authors: W
authors: Guo
authors: Chan
authors: C
authors: Zhang
authors: Xiaoyuan
authors: X
authors: Wang
mesh_terms: D000217:Acyltransferases / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D044083:Cronobacter sakazakii / Q000201:enzymology* / Q000235:genetics*; D004269:DNA, Bacterial / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D008050:Lipid A / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010957:Plasmids; D016133:Polymerase Chain Reaction / Q000379:methods
chemical_list: D004269:DNA, Bacterial; D008050:Lipid A; D000217:Acyltransferases