marthii and L. rocourtiae, LY2157299 order for further evaluating and supplementing this assay. Furthermore, this approach has the potential to contribute to a more comprehensive taxonomy
platform for the Listeria genus and is suitable for use in epidemiological research and classification of bacteria. Grant numbers and sources of support: this work was supported by Science Foundation for The Excellent Youth Scholars of Health Bureau of Zhejiang Province (2008QN007). The authors wish it to be known that, in their opinion, the authors D.J. and Y.L. should be regarded as the joint first authors. “
“Phenyl lactic acid (PLA) has been widely reported as a new natural antimicrobial compound. In this study, 120 Lactobacillus plantarum strains were demonstrated to produce PLA using high-performance liquid chromatography.
Lactobacillus plantarum IMAU10124 was screened with a PLA yield of 0.229 g L−1. Compared with all previous reports, this is the highest PLA-producing lactic acid bacteria (LAB) when grown in MRS broth without any optimizing conditions. When 3.0 g L−1 phenyl pyruvic acid (PPA) was added to the medium as substrate, PLA production reached 2.90 g L−1, with the highest 96.05% conversion rate. A lowest PLA-yielding L. plantarum IMAU40105 (0.043 g L−1) was also screened. It was shown that the conversion from PPA to PLA by lactic dehydrogenase (LDH) is the key factor check details in the improvement of PLA production by LAB. Comparing the LDH gene of two strains, four amino acid mutation sites were found in this study in the LDH of L. plantarum IMAU10124. “
“Mycoplasma mycoides subsp. mycoides (Mmm) strain Afadé had previously been shown to undergo spontaneous phase variations between an opaque capsulated variant and a translucent (TR) variant devoid of a capsule but able to secrete cell-free exopolysaccharides. This phase variation is associated with an ON/OFF genetic switch in a glucose permease gene. In this study, in vivo and in vitro assays were conducted to compare the virulence of the two variants and their abilities to resist host defence. Capsulated variants
were shown, in a mouse model, to induce longer bacteraemia that was correlated with better serum resistance in vitro. In contrast, TR variants displayed better ability to adhere to an inert support, linked to the absence of a capsule, Phenylethanolamine N-methyltransferase changes in cell surface hydrophobicity and increased resistance to antimicrobial peptide and hydrogen peroxide. The switch from one variant population to another, which was observed both in vivo and in vitro under stress conditions, is further discussed as a means for Mmm to modulate its interactions with animal hosts during different stages of the disease. “
“RodZ (YfgA) is a membrane protein well conserved among bacterial species and important in the determination of cell shape and motility, although the molecular mechanism involved is not well established.