deciphering the acylation pattern of yersinia enterocolitica lipid a解密的酰化模式就要enterocolitica脂质.pdfVIP

Deciphering the Acylation Pattern of Yersinia enterocolitica Lipid A ´ 1,2 1 ¨ ¨ 3 ´ ´ 1 1 Mar Reines , Enrique Llobet , Kathe M. Dahlstrom , Camino Perez-Gutierrez , Catalina M. Llompart , 1 3 ´ 1,2 Nuria Torrecabota , Tiina A. Salminen , Jose A. Bengoechea * ´ ´ ` 1 Laboratory Microbial Pathogenesis, Fundacio d’Investigacio Sanitaria de les Illes Balears (FISIB), Recinto Hospital Joan March, Bunyola, Spain, 2 Consejo Superior de ˚ ´ Investigaciones Cientıficas (CSIC), Madrid, Spain, 3 Structural Bioinformatics Laboratory, Department of Biosciences, Abo Akademi University, Turku, Finland Abstract Pathogenic bacteria may modify their surface to evade the host innate immune response. Yersinia enterocolitica modulates its lipopolysaccharide (LPS) lipid A structure, and the key regulatory signal is temperature. At 21uC, lipid A is hexa-acylated and may be modified with aminoarabinose or palmitate. At 37uC, Y. enterocolitica expresses a tetra-acylated lipid A consistent with the 39-O-deacylation of the molecule. In this work, by combining genetic and mass spectrometric analysis, we establish that Y. enterocolitica encodes a lipid A deacylase, LpxR, responsible for the lipid A structure observed at 37uC. Western blot analyses indicate that LpxR exhibits latency at 21uC,