pneumoniae-infected patients and His tag antibodies by Western bl

pneumoniae-infected patients and His tag antibodies by Western blot. There was no cross-reactivity between the anti-recombinant proteins serum and other respiratory antigens. A total of 400 patients were investigated, their respiratory specimens tested by PCR, and sera tested by a commercial test kit; 56 with positive sera and positive respiratory specimens were designated as standard positive serum and 63 patients were designated as standard negative serum. The purified recombinant proteins were used as a combination of antigens or separately

to test the serum. Serological test demonstrated that rP1-513 of the C terminal of P1 adhesin is a new candidate antigen with greater sensitivity and specificity for IgG and IgM serodiagnosis of M. pneumoniae-infected

patients. The results confirmed that rP1-513 could be a useful new antigen for the immunodiagnosis of M. pneumoniae infection. “
“National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan Conjugative plasmid transfer systems have been well studied, but very little is known about the recipient factors that control horizontal transmission. A self-transmissible IncP-9 naphthalene catabolic plasmid, NAH7, carries the traF gene, whose product is considered to be a host-range modifier of NAH7, because its traF deletion mutant (NAH7dF) is transmissible from Pseudomonas putida to P. putida and Escherichia coli and from E. coli to E. coli, but not from E. coli to P. putida. In this study, transposon mutagenesis of P. putida KT2440 was performed to isolate the mutants that could receive NAH7dF from E. coli. Alectinib The mutants had the transposon insertions in ptsP or ptsO, encoding two of three components of the nitrogen-related phosphotransferase system (PTSNtr). The KT2440 derivative lacking ptsN, encoding the remaining component of PTSNtr, was also able to receive NAH7dF. These results

indicated that Plasmin the PTSNtr in P. putida is involved in inhibition of conjugative transfer of NAH7dF from E. coli. Our further experiments using site-directed mutants suggested the indirect involvement of the phosphorylated form of PtsO in the inhibition of the conjugative transfer. Conjugative transfer of NAH7 and another IncP-9 plasmid, pWW0, from E. coli was partially inhibited by the PtsO function in KT2440. “
“Only a few plasmid-borne AmpC (pAmpC) β-lactamases, such as CMY-2, can account for carbapenem resistance in Enterobacteriaceae in combination with outer membrane impermeability. The aim of this study was to elucidate the contribution of Asn-346, which is well conserved among carbapenem-hydrolyzing pAmpCs, to the hydrolysis spectrum of CMY-2. Site-directed mutagenesis experiments were carried out to replace Asn-346 with glycine, alanine, valine, glutamate, aspartate, serine, threonine, glutamine, tyrosine, isoleucine, lysine, and histidine.

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