Variation and inheritance of the Xanthomonas raxX-raxSTAB gene cluster required for activation of XA21-mediated immunity

The rice XA21-mediated immune response is activated on recog-nition of the RaxX peptide produced by the bacterium Xanthomonas oryzae pv. oryzae (Xoo). The 60-residue RaxX pre-cursor is post-translationally modified to form a sulfated tyrosine peptide that shares sequence and functional similarity with the plant sulfated tyrosine (PSY) peptide hormones. The 5-kb raxX-raxSTAB gene cluster of Xoo encodes RaxX, the RaxST tyrosyl-protein sulfotransferase, and the RaxA and RaxB components of a predicted type I secretion system. To assess raxX-raxSTAB gene cluster evolution and to determine its phylogenetic distribution, we first identified rax gene homologues in other genomes. We detected the complete raxX-raxSTAB gene cluster only in Xanthomonas spp., in five distinct lineages in addition to X.ory-zae. The phylogenetic distribution of the raxX-raxSTAB gene cluster is consistent with the occurrence of multiple lateral (hori-zontal) gene transfer events during Xanthomonas speciation. RaxX natural variants contain a restricted set of missense substi-tutions, as expected if selection acts to maintain peptide hor-mone-like function. Indeed, eight RaxX variants tested all failed to activate the XA21-mediated immune response, yet retained peptide hormone activity. Together, these observations support the hypothesis that the XA21 receptor evolved specifically to rec-ognize Xoo RaxX.This study was supported by Public Health Service research grants GM059962 and GM122968 from the National Institute of General Medical Sciences awarded to P.C.R

Seasonal variation in the behavior of captive alpine musk deer, Moschus sifanicus, in Xinglongshan Musk Deer Farm, of China

Musk deer farming has the potential to be an effective conservation tool for the protection of musk deer as well as the production of valuable musk. To be successful, this requires a thorough understanding of the behavior of captive musk deer in order to improve their reproductive success and management. Between August 2005 to January 2006, the behavior sampling of 19 male and 13 female captive alpine musk deer, Moschus sifanicus Büchner, 1891, was used to examine the durations of twelve behavioral characteristics during the pre-rut (August to October) and rut seasons (November to January). Both males and females exhibited some seasonal variation in behavior. Males rested and fed more during the pre-rut than the rut and spent more time walking, fighting, and standing alert during the rut. Females spent more time feeding, ruminating, and interacting non-aggressively with other individuals during the pre-rut and more time in agonistic interactions during the rut. The significance of these behavioral changes and their association with husbandry practices and farm management are discussed

Purification and Structural Analysis of the Effective Anti-TMV Compound ε-Poly-<span style="font-variant: small-caps">l</span>-lysine Produced by <i>Streptomyces ahygroscopicus</i>

Microbial secondary metabolites produced by actinomycetes are important natural products widely applied to control plant diseases. A variety of actinomycetes were isolated from soil samples collected from Tianzhu Mountain in Shenyang, China. A Streptomyces strain Shenyang Tianzhu (STZ) exhibits effective antiviral activity against Tobacco mosaic virus (TMV). The isolate was identified as Streptomyces ahygroscopicus based on its cultural, morphological, physiological, biochemical characteristics as well as the phylogenetic analysis using 16S rRNA sequences. To obtain the pure anti-TMV compound from Streptomyces STZ, the culture broth was subjected to Amberlite IRC-50 ion-exchange resin, SX-8 macroporous adsorption resin and Sephadex G-25 gel column chromatography. The purified active compound was confirmed to be &#949;-poly-l-lysine (&#949;-PL), with molecular mass in the range of 3454&#8211;4352 Da by structural analysis with infrared (IR), matrix-assisted laser desorption ionization-time-of-flight MS (MALDI-TOF), thin-layer chromatography (TLC) and high-resolution magic angle spinning nuclear magnetic resonance (HR-MAS NMR). The protective and curative effects of the purified compound &#949;-PL were tested and the results showed that the compound exhibited significant protective and curative activity against TMV. The potential application of &#949;-PL as an efficient anti-plant virus agent was expected

Revised Taxonomic Binomials Jeopardize Protective Wildlife Legislation

Due to revised phylogenies and newly discovered biogeographic distributions, scientific binomials are being amended continuously. Problematic is that wildlife protection legislation tends not to keep pace with these reappraisals, creating a wide range of legislative loopholes and potentially compromising ability to prosecute illegal wildlife trade (IWT). This serious and growing international problem proves particularly challenging in China because binomials used on China's national legislation have not been up-dated since 1989, alongside the enormous issues of IWT in this mega-diverse nation. Here we focus especially on mammals, because these support lucrative criminal markets and receive the greatest international policing efforts; however all protected taxa are vulnerable to this mis-naming ambiguity. To-date, the names of twenty-five threatened species, including eighteen mammals, have become incongruent with Chinese law. Additionally, two primate species, newly discovered within China, have not yet been incorporated into Chinese law. A further, six mammalian species are known by different synonyms between Chinese law and CITES, hindering international policing and compilation of data on IWT. Taxonomic revisions similarly undermine legislation in other mega-diverse countries; posing a critical risk to wildlife protection worldwide. We recommend that scientific binomials must be updated systematically across all 181 CITES signatory nations

Oxidative Cyclization of 2-Aryl-3-arylamino-2-alkenenitriles to <i>N</i>-Arylindole-3-carbonitriles Mediated by NXS/Zn(OAc)₂

A variety of 2-aryl-3-arylamino-2-alkenenitriles were converted to <i>N</i>-arylindole-3-carbonitriles in a one-pot manner through NBS- or NCS-mediated halogenation followed by Zn(OAc)₂-catalyzed intramolecular cyclization. It is postulated that the process involves the formation of arylnitrenium ion intermediates, which undergo the electrophilic aromatic substitution to give the cyclized <i>N</i>-arylindole product

Table_1_Causal effects of gut microbiota on the prognosis of ischemic stroke: evidence from a bidirectional two-sample Mendelian randomization study.XLSX

BackgroundIncreasing research has implicated the possible effect of gut microbiota (GM) on the prognosis of ischemic stroke (IS). However, the precise causal relationship between GM and functional outcomes after IS remains unestablished.MethodsData on 211 GM taxa from the MiBioGen consortium and data on prognosis of IS from the Genetics of Ischemic Stroke Functional Outcome (GISCOME) network were utilized as summary-level data of exposure and outcome. Four kinds of Mendelian randomization (MR) methods were carried out to ascertain the causal effect of GM on functional outcomes following IS. A reverse MR analysis was performed on the positive taxa identified in the forward MR analysis to determine the direction of causation. In addition, we conducted a comparative MR analysis without adjusting the baseline National Institute of Health Stroke Scale (NIHSS) of post-stroke functional outcomes to enhance confidence of the results obtained in the main analysis.ResultsFour taxa were identified to be related to stroke prognosis in both main and comparative analyses. Specifically, genus Ruminococcaceae UCG005 and the Eubacterium oxidoreducens group showed significantly negative effects on stroke prognosis, while the genus Lachnospiraceae NK4A136 group and Lachnospiraceae UCG004 showed protective effects against stroke prognosis. The reverse MR analysis did not support a causal role of stroke prognosis in GM. No evidence of heterogeneity, horizontal pleiotropy, and outliers was found.ConclusionThis MR study provided evidence that genetically predicted GM had a causal link with post-stroke outcomes. Specific gut microbiota taxa associated with IS prognosis were identified, which may be helpful to clarify the pathogenesis of ischemic stroke and making treatment strategies.</p