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Abstract: Attempts were made to establish one-step multiplex PCR assay for the identification of the widely used species in deer products (sika deer, wapiti, red deer and reindeer). Primers were designed from tandem repeat region of D-loop and well-conserved region of 16S rDNA after alignment of the available sequences in the GenBank database. The primers generated specific fragments of 307bp in length for sika deer, 307 and 246bp for wapiti, 272bp for Tarim red deer, 230bp for red deer and 141bp for reindeer, respectively. The detection limit was 0.05ng for sika deer and wapiti, 0.1ng for Tarim red deer, 0.5ng for red deer and 0.02ng for reindeer. The results demonstrated that the fraudulent phenomenon is epidemic in the substitution of deer products, in especially antler, penis, foetus and tendon products. Hence, this multiplex PCR provided a useful and sensitive technique to identify the sources of deer products. [Copyright &y& Elsevier]

ArgR, a transcriptional regulator belonging to the AraC/XylS family, plays a key role in arginine metabolism regulation. ArgR has also been found to repress the transcription of a lipase gene, but its molecular mechanism is still unknown. In this study, we investigated the molecular mechanism acting on the expression of intracellular lipase gene lipA regulated by ArgR in Pseudomonas protegens Pf-5 through knockout and overexpression of argR , detection of DNA-protein interaction in vivo , determining whole-cell lipase activities of various strains derived from Pf-5, and examining β-galactosidase activities of various lacZ fusions. The results demonstrated that ArgR inhibits lipA expression at the transcriptional level. Further results showed that the inhibition of lipA transcription by ArgR is mediated by binding to the ArgR binding site of lipA promoter to produce steric hindrance, in which the common sequence, TGTCGC is crucial for the ArgR binding. Besides, arginine inhibits lipA expression in both wild-type and argR mutant, and shows a synergistic inhibition on lipA expression when combined with ArgR. To the best of our knowledge, this is the first report on ArgR directly repressing the transcription of a lipase gene. • ArgR directly inhibits lipA transcription by binding to lipA promoter. • lipA promoter includes an ArgR binding site bound by ArgR. • Arginine represses lipA expression in both wild-type and argR knockout mutant. [ABSTRACT FROM AUTHOR]

A novel actinobacterium, designated strain JXJ CY 19T, was isolated from a culture mat of Microcystis aeruginosa FACHB-905 collected from Dianchi Lake, South-west China. 16S rRNA gene sequences comparison of strain JXJ CY 19T and the available sequences in the GenBank database showed that the strain was closely related to Modestobacter marinus 42H12-1T (99.1% similarity) and Modestobacter roseus KLBMP 1279T (99.0%). The isolate had meso-diaminopimelic in the cell wall with whole-cell sugars of mannose, rhamnose, ribose, glucose, galactose, and arabinose. The menaquinone detected was MK-9(H4), while the major cellular fatty acids include C17:1 ω8c, C15:0 iso, C15:1 iso G and C16:0 iso. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and an unidentified phospholipid. The DNA-DNA hybridization values between strains JXJ CY 19T and the closely related type strains Modestobacter marinus CGMCC 4.5581T and Modestobacter roseus NBRC 108673T were determined to be 50.8 ± 0.8% and 44.1 ± 1.7%, respectively. The DNA G+C content was 71.9 mol%. On the basis of the above taxonomic data and differences in physiological characters from the closely related type strains, strain JXJ CY 19T was recognized as a novel species of the genus Modestobacter, for which the name Modestobacter lacusdianchii sp. nov. (JXJ CY 19T = KCTC 39600T = CPCC 204352T) is proposed. The type strain JXJ CY 19T can solubilize calcium phosphate tribasic (Ca3(PO4)2), phytin and L-α-phosphatidylcholine. The phosphate-solubilizing property of the novel actinobacterium could be a possible factor for the increase in growth of Microcystis aeruginosa FACHB-905 in ecosystem where the amount of available soluble phosphate is limited such as Dianchi Lake. [ABSTRACT FROM AUTHOR]

An antialgal compound was isolated from the cultured broth of Streptomyces jiujiangensis JXJ 0074 by using bioassay methods. Based on the data of H-NMR, C-NMR, ESI-MS, and thin layer chromatography, the active compound was identified as L-valine, which showed antialgal activity mainly against Microcystis. L-valine exhibited greater antialgal activities than both L-lysine and copper sulfate (CuSO) did on Microcystis aeruginosa lawn. However, M. aeruginosa recovered growth earlier with higher growth rate in L-valine treatment than in L-lysine treatment. L-valine dissipated completely within 2 days, much quicker than L-lysine (6 days), which resulted in the lysing of more than 80 % M. aeruginosa cells and the release of amount of intracellular microcystin-LR (MC-LR) within 2 days. As a resultant, the extracellular MC-LR content was more than twice of the control from day 1 to 5. Exposure to L-valine significantly promoted the synthesis of MC-LR. L-lysine also promoted the release and synthesis of MC-LR with much lesser efficiency than L-valine. L-valine could damage Microcystis severely, causing perforation and collapse of M. aeruginosa cells and decrease of the chlorophyll. The superoxide dismutase (SOD) activity in L-valine-treated cells of M. aeruginosa initially increased with 32.94 ± 3.37 % higher than the control after 36 h and then decreased quickly. However, the increase rate of superoxide anion radical (O) was much higher than that of SOD, which resulted in serious lipid peroxidation and accumulation of malondialdehyde (MDA). To our knowledge, this is the first report showing L-valine active against cyanobacteria. [ABSTRACT FROM AUTHOR]