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Tu J.,Sichuan Agricultural University | Li D.,Sichuan Agricultural University | Li Q.,Yunnan Normal University | Li Q.,Kunming Xianghao Technology Co. | And 8 more authors.
Evolutionary Bioinformatics | Year: 2015

Vertebrate b-defensins comprise an important family of antimicrobial peptides that protect organisms from a diverse spectrum of bacteria, viruses, fungi, and protozoan parasites. Previous studies have shown a marked variation in the number of b-defensins among species, but the underlying reason is unclear. To address this question, we performed comprehensive computational searches to study the intact b-defensin genes from 29 vertebrates. Phylogenetic analysis of the b-defensin genes in vertebrates identified frequent changes in the number of b-defensin genes and multiple species-specific gene gains and losses that have been occurring throughout the evolution of vertebrates. The number of intact b-defensin genes varied from 1 in the western clawed frog to 20 in cattle, with numerous expansions and contractions of the gene family throughout vertebrates, especially among tetrapods. The b-defensin gene number in a species is relevant to the ever-changing microbial challenges from the environment that they inhabit. Selection pressure analysis shows there exist three amino acid sites under significant positive selection. Protein structural characteristics analysis suggests that structural diversity determines the diverse functions of b-defensins. Our study provides a new perspective on the relationships among vertebrate b-defensin gene repertoires and different survival circumstances, which helps explain how b-defensins have evolved © the authors, publisher and licensee Llibertas Aacademica Llimited.


Duan Y.-Q.,China Tobacco Yunnan Industrial Co. | Zhou X.-K.,China Tobacco Yunnan Industrial Co. | Zhou X.-K.,Southwest forestry University | Di-Yan L.,Sun Yat Sen University | And 9 more authors.
Antonie van Leeuwenhoek, International Journal of General and Molecular Microbiology | Year: 2015

A Gram-stain negative, motile, rod-shaped bacterium, designated strain YIM Hb-3T, was isolated from the stem of a tobacco plant. The strain was observed to form convex, circular and yellow-colored colonies. The predominant respiratory quinone was identified as Q-8. The major fatty acids (>5 %) detected were C16:1ω7c and/or C16:1ω6c (summed feature 3), C16:0, C17:0cyclo, C18:1ω7c and/or C18:1ω6c (summed feature 8), C14:03-OH and/or iso-C16:1I (summed feature 2), C14:0 and C12:0. The genomic DNA G+C content was determined to be 54.8 mol%. Phylogenetic trees based on 16S rRNA gene sequences and multilocus sequence analysis showed that strain YIM Hb-3T had the closest phylogenetic relationship with Enterobacter mori LMG 25706T. DNA–DNA relatedness value between strain YIM Hb-3T and E. mori LMG 25706T was 46.9 ± 3.8 %. On the basis of phenotypic and chemotaxonomic data, phylogenetic analysis, and DNA–DNA relatedness value, strain YIM Hb-3T is considered to represent a novel species of the genus Enterobacter, for which the name Enterobacter tabaci sp. nov. is proposed. The type strain is YIM Hb-3T (=KACC 17832T =KCTC 42694T). © 2015, Springer International Publishing Switzerland.


Hu L.,Yunnan Nationalities University | Hu L.,Kunming Xianghao Technology Co. | Chen N.-N.,Yunnan Nationalities University | Feng L.,Southwest forestry University | And 4 more authors.
Biochemical Systematics and Ecology | Year: 2014

This paper reports the isolation and characterization of seven piceatannol derivatives (1 - 7), including two new compounds (4 and 6), along with resveratrol (8) and polydatin (9), from the underground parts of Rheum austral D. Don collected from Tibet. The structures of the isolates were identified based on analysis of their spectroscopic data and comparison with literature. Compounds 3-. 7, piceatannol-4'-O-glucopyranoside and its 6″-O-acylated derivatives reported in this study may be useful chemotaxonomic markers for R. austral collected from Tibet. © 2014 Elsevier Ltd.


Hu L.,Yunnan Nationalities University | Hu L.,Kunming Xianghao Technology Co. | Chen N.-N.,Yunnan Nationalities University | Hu Q.,Kunming Xianghao Technology Co. | And 3 more authors.
Molecules | Year: 2014

A novel dimer of piceatannol glycoside, named rheumaustralin (1) was isolated from the underground parts of the ethnomedicinal plant Rheum austral (Polygonaceae) collected from Tibet together with 17 known compounds, including rheumin (2), 2,5-dimethyl-7-hydroxychromone (3), 2,5-dimethylchromone-7-O- β-D-glucopyranoside (4), 7-hydroxy-2-(2′-hydroxypropyl)-5- methylchromone (5), torachrysone (6) torachrysone-8-O-β-D-glucopyranoside (7), 4-(4′-hydroxyphenyl)-2-butanone-4′-O-β-D-glucopyranoside (8), amabiloside (9), N-trans-feruloyl tyramine (10), chrysophanol (11), aloe-emodin (12), emodin (13), physcion (14), physcion-1-O-β-D- glucopyranoside (15), emodin-8-O-β-D-glucopyranoside (16), D-catechin (17) and gallic acid (18). Their structures were determined by combined spectroscopic methods and by comparison of their spectral data with those reported in literature. Compounds 1-10 were tested for their ability to scavenge 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical. © 2014 by the authors.


Liu W.-B.,Yunnan Nationalities University | Hu L.,Yunnan Nationalities University | Hu L.,Kunming Xianghao Technology Co. | Hu Q.,Kunming Xianghao Technology Co. | And 3 more authors.
Molecules | Year: 2013

Two new resveratrol trimer derivatives, named rheumlhasol A (1) and rheumlhasol B (2) were isolated from the methanolic extract of roots of Rheum lhasaense A. J. Li et P. K. Hsiao together with four known resveratrol dimer derivatives, including maximol A (3), gnetin C (4), ε-viniferin (5), and pallidol (6). The structures were determined by combined spectroscopic methods and by comparison of their spectral data with those reported in the literature. All the compounds isolated from R. lhasaense were tested for their ability to scavenge1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. © 2013 by the authors.

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