I at position two (2Oacetylation) confers serotypes 1b, 3a, 3b, 4b, and 7b with group issue six (six, 18, 19). Glucosylation is mediated by three genes (gtrA, gtrB, and gtr [type specific]) that happen to be arranged inside a single operon generally known as the gtr cluster, which is encoded by serotype conversion bacteriophages, with six such bacteriophages identified to date (SfI, SfIC, SfII, SfIV, SfV, and SfX) (205). 2OAcetylation of RhaI is performed by a particular Oacetyltransferase enScoded by the gene oac (18, 19), which can be also carried by the serotype conversion bacteriophage Sf6 (26). Phosphorylation together with the PEtN of RhaIII and/or RhaII at position three was not too long ago identified in the newly proposed S. flexneri serotypes 4av, Xv, and Yv (4, 5, 15, 27) and possibly in atypical strains of serotypes four, 6, and 4X (92) and was demonstrated to confer the hosts together with the MASF IV1 (E1037) antigenic determinant. The plasmid carrying gene opt (Oantigen phosphoethanolamine transferase) mediates the PEtN modification in these serotypes (4, 5, 15, 17). Recently, however another Oantigen modification, namely, the addition of an Oacetyl group to RhaIII at position 3 or four (3/4Oacetylation), was recognized in S. flexneri serotypes 1a, 1b, 2a, 5a, and Y and in serotype 6 as obtaining a unique basal Oantigen structure (16, 280). The new Oacyltransferase oacB gene mediates the 3/4Oacetylation in serotypes 1a, 1b, 2a, 5a, and Y but not in serotype six (31). The oacB gene is carried by a transposonlike structure positioned upstream in the adrA gene on the chromosome (31). The 3/4Oacetylation on RhaIII interferes with glucoReceived 20 January 2014 Returned for modification 6 March 2014 Accepted 21 March 2014 Published ahead of print 26 March 2014 Editor: D. J. Diekema Address correspondence to Qiangzheng Sun, sunqiangzheng@icdc.Formula of 1190861-74-5 cn. J.W., R.L., and Y.A.K. contributed equally to this operate. Copyright 2014, American Society for Microbiology. All Rights Reserved. doi:ten.1128/JCM.00197June 2014 Volume 52 NumberJournal of Clinical Microbiologyp. 2033jcm.asm.orgWang et al.two) LRhapIII(1 two) LRhapII(1 3) LRhapI(1 three) DGlcpNAc(1 3/4 OAc( 60 /20 ) 3 DGlcp 4 DGlcp four DGlcp2) LRhapIII(1 two) LRhapII(1 3) LRhapI(1 3) DGlcpNAc(FIG 1 OAntigen structures of immunizing strain S.212127-80-5 custom synthesis flexneri 51251_pSQZ4 and absorbing strain S.PMID:33721109 flexneri 51251 used for the preparation of grouping antiserum 9.sylation (group aspect 7,eight) and PEtN phosphorylation (group factor IV1) of the same sugar residue mediated by the gtrX gene cluster plus the opt gene, respectively, resulting within the loss in the 7,8 determinant or even a lower within the amount of the MASF IV1 determinant manifestation (17). In this perform, we studied the distribution of your 3/4Oacetylation in S. flexneri by PCR screening of your oacB gene and serological assay using a particular absorbed antiserum, and we found that this Oantigen modification is widespread in serotypes 1a, 1b, 2a, 5a, and Y and confers the host using a novel antigenic determinant provisionally named issue 9.Materials AND METHODSEthics statement. This study was reviewed and approved by the ethics committee from the National Institute for Communicable Illness Control and Prevention, China CDC. Strains and culturing situations. S. flexneri strain 51251 carrying vector pSQZ4 (51251_pSQZ4) (31), which possesses the 3/4Oacetylation on RhaIII inside the O antigen, was used because the immunizing strain (Fig. 1). S. flexneri 51251 (31), the parent strain of transformant 51251_pSQZ4, which lacked the 3/4Oacetylation on RhaIII (Fig. 1).