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31.
Strong and stable geographic differentiation of swamp buffalo maternal and paternal lineages indicates domestication in the China/Indochina border region 总被引:2,自引:0,他引:2 下载免费PDF全文
Yi Zhang Yongfang Lu Marnoch Yindee Kuan‐Yi Li Hsiao‐Yun Kuo Yu‐Ten Ju Shaohui Ye Md Omar Faruque Qiang Li Yachun Wang Vu Chi Cuong Lan Doan Pham Bounthong Bouahom Bingzhuang Yang Xianwei Liang Zhihua Cai Dianne Vankan Wallaya Manatchaiworakul Nonglid Kowlim Somphot Duangchantrasiri Worawidh Wajjwalku Ben Colenbrander Yuan Zhang Peter Beerli Johannes A. Lenstra J. Stuart F. Barker 《Molecular ecology》2016,25(7):1530-1550
The swamp type of the Asian water buffalo is assumed to have been domesticated by about 4000 years BP, following the introduction of rice cultivation. Previous localizations of the domestication site were based on mitochondrial DNA (mtDNA) variation within China, accounting only for the maternal lineage. We carried out a comprehensive sampling of China, Taiwan, Vietnam, Laos, Thailand, Nepal and Bangladesh and sequenced the mtDNA Cytochrome b gene and control region and the Y‐chromosomal ZFY, SRY and DBY sequences. Swamp buffalo has a higher diversity of both maternal and paternal lineages than river buffalo, with also a remarkable contrast between a weak phylogeographic structure of river buffalo and a strong geographic differentiation of swamp buffalo. The highest diversity of the swamp buffalo maternal lineages was found in south China and north Indochina on both banks of the Mekong River, while the highest diversity in paternal lineages was in the China/Indochina border region. We propose that domestication in this region was later followed by introgressive capture of wild cows west of the Mekong. Migration to the north followed the Yangtze valley as well as a more eastern route, but also involved translocations of both cows and bulls over large distances with a minor influence of river buffaloes in recent decades. Bayesian analyses of various migration models also supported domestication in the China/Indochina border region. Coalescence analysis yielded consistent estimates for the expansion of the major swamp buffalo haplogroups with a credibility interval of 900 to 3900 years BP. The spatial differentiation of mtDNA and Y‐chromosomal haplotype distributions indicates a lack of gene flow between established populations that is unprecedented in livestock. 相似文献
32.
Cuong Quang Le Mercy Oyugi Ebenezer Joseph Toan Nguyen Md Hasmat Ullah Joshua Aubert Thien Phan Joseph Tran Kayunta Johnson-Winters 《Biochemistry and Biophysics Reports》2017
F420H2:NADP+ Oxidoreductase (Fno) catalyzes the reversible reduction of NADP+ to NADPH by transferring a hydride from the reduced F420 cofactor. Here, we have employed binding studies, steady-state and pre steady-state kinetic methods upon wtFno and isoleucine 135 (I135) Fno variants in order to study the effects of side chain length on the donor-acceptor distance between NADP+ and the F420 precursor, FO. The conserved I135 residue of Fno was converted to a valine, alanine and glycine, thereby shortening the side chain length. The steady-state kinetic analysis of wtFno and the variants showed classic Michaelis-Menten kinetics with varying FO concentrations. The data revealed a decreased kcat as side chain length decreased, with varying FO concentrations. The steady-state plots revealed non-Michaelis-Menten kinetic behavior when NADPH was varied. The double reciprocal plot of the varying NADPH concentrations displays a downward concave shape, while the NADPH binding curves gave Hill coefficients of less than 1. These data suggest that negative cooperativity occurs between the two identical monomers. The pre steady-state Abs420 versus time trace revealed biphasic kinetics, with a fast phase (hydride transfer) and a slow phase. The fast phase displayed an increased rate constant as side chain length decreased. The rate constant for the second phase, remained ~2 s?1 for each variant. Our data suggest that I135 plays a key role in sustaining the donor-acceptor distance between the two cofactors, thereby regulating the rate at which the hydride is transferred from FOH2 to NADP+. Therefore, Fno is a dynamic enzyme that regulates NADPH production. 相似文献
33.
Mark Hamann Chu The Cuong Nguyen Duy Hong Pham Thuoc Bui Thi Thuhien 《Biodiversity and Conservation》2006,15(11):3703-3720
To establish baseline data on the distribution, abundance and threats to marine turtles in Viet Nam we conducted surveys with
local fishers, community members and provincial Ministry of Fisheries staff from 17 of Viet Nam’s 29 coastal provinces. These
data indicate that five species of marine turtle reside in Viet Nam’s waters (loggerhead, olive ridley, leatherback, green
and hawksbill turtles), and four species nest on Viet Nam’s beaches (all of the above except the loggerhead turtle). It is
evident from these data that significant declines have occurred in both foraging and nesting populations of all five marine
turtle species found in Viet Nam. The greatest current threats to marine turtle populations in Viet Nam are habitat degradation,
the accidental and opportunistic of turtles capture by fishers and the direct take of nesting females and their eggs. Successful
conservation efforts have been made in recent years through collaboration between international Non Government Organisations
and several Vietnamese Government Ministries. Continued success of these projects and the development and implementation of
marine conservation policy will depend upon building awareness among Government employees, fishers and the general public
about marine turtle biology, ecology, and the need to protect them. 相似文献
34.
Xuan Cuong Mai Chia-Rui Shen Chao-Lin Liu Dang Mau Trinh Minh Ly Nguyen 《Journal of phycology》2023,59(4):775-784
Species identification of Scenedesmus-like microalgae, comprising Desmodesmus, Tetradesmus, and Scenedesmus, has been challenging due to their high morphological and genetic similarity. After developing a DNA signaturing tool for Desmodesmus identification, we built a DNA signaturing database for Tetradesmus. The DNA signaturing tool contained species-specific nucleotide sequences of Tetradesmus species or strain groups with high similarity in ITS2 sequences. To construct DNA signaturing, we collected data on ITS2 sequences, aligned the sequences, organized the data by ITS2 sequence homology, and determined signature sequences according to hemi-compensatory base changes (hCBC)/CBC data from previous studies. Four Tetradesmus species and 11 strain groups had DNA signatures. The signature sequence of the genus Tetradesmus, TTA GAG GCT TAA GCA AGG ACCC, recognized 86% (157/183) of the collected Tetradesmus strains. Phylogenetic analysis of Scenedesmus-like species revealed that the Tetradesmus species were monophyletic and closely related to each other based on branch lengths. Desmodesmus was suggested to split into two subgenera due to their genetic and morphological distinction. Scenedesmus must be analyzed along with other genera of the Scenedesmaceae family to determine their genetic relationships. Importantly, DNA signaturing was integrated into a database for identifying Scenedesmus-like species through BLAST. 相似文献
35.
36.
Nguyen Huy Thuan Nguyen Thanh Trung Nguyen Xuan Cuong Duong Van Cuong Dong Van Quyen Sailesh Malla 《World journal of microbiology & biotechnology》2018,34(6):75
In bio-based fermentation, the overall bioprocess efficiency is significantly affected by the metabolic burden associated with the expression of complete biosynthetic pathway as well as precursor and cofactor generating enzymes into a single microbial cell. To attenuate such burden by compartmentalizing the enzyme expression, recently synthetic biologists have used coculture or poly-culture techniques for biomolecules synthesis. In this paper, coculture system of two metabolically engineered Escherichia coli populations were employed which comprises upstream module expressing two enzymes converting para-coumaric acid into resveratrol and the downstream module expressing glucosyltransferase to convert the resveratrol into its glucosidated forms; polydatin and resveratroloside. Upon optimization of the initial inoculum ratio of two E. coli populations, 92 mg resveratrol glucosides/L (236 µM) was produced i.e. achieving 84% bioconversion from 280 µM of p-coumaric acid in 60 h by 3 L fed batch fermentor. This is the report of applying coculture system to produce resveratrol glucosides by expressing the aglycone formation pathway and sugar dependent pathway into two different cells. 相似文献
37.
Mette Haubjerg Nicolaisen Nguyen Duc Cuong Jakob Herschend Birgit Jensen Le Cam Loan Pham Van Du Jan Sørensen Helle Sørensen Stefan Olsson 《BioControl》2018,63(6):843-853
A pathogenicity assay for in planta screening of biological control agents (BCAs) towards sheath blight in rice was developed, and used to evaluate a panel of Rhizoctonia solani Kühn hyphae-associated bacteria for their ability to control sheath blight under screenhouse conditions. The best performing BCA, Burkholderia sp. strain A-7.3, was selected for field trials. Disease incidence and disease severity were significantly reduced leading to a significant grain yield increase of 7%. Furthermore, R. solani sclerotia formation and sclerotia viability were significantly reduced, thus lowering the reservoir for primary infections in the next crop cycle. The paper presents a reliable pathogenicity assay that can be used to test BCA performance under different scenarios e.g. plant variety and soil conditions, and help predict translation of results obtained under screenhouse conditions to field performance. Furthermore, it supports the hypothesis that hyphae-associated bacteria are a promising source of niche-specific BCAs towards fungal pathogens. 相似文献
38.
Bach Xuan Tran Long Hoang Nguyen Lan Phuong Nguyen Cuong Tat Nguyen Huong Thi Thu Phan Carl A. Latkin 《PloS one》2016,11(4)
BackgroundMethadone maintenance treatment (MMT) reduces HIV risk behaviors and improves access to HIV-related services among drug users. In this study, we assessed the uptake and willingness of MMT patients to refer HIV testing and counseling (HTC) service to their sexual partners and relatives.MethodsHealth status, HIV-related risk behaviors, and HTC uptake and referrals of 1,016 MMT patients in Hanoi and Nam Dinh were investigated. Willingness to pay (WTP) for HTC was elicited using a contingent valuation technique. Interval and logistic regression models were employed to determine associated factors.ResultsMost of the patients (94.2%) had received HTC, 6.6 times on average. The proportion of respondents willing to refer their partners, their relatives and to be voluntary peer educators was 45.7%, 35.3%, and 33.3%, respectively. Attending MMT integrated with HTC was a facilitative factor for HTC uptake, greater WTP, and volunteering as peer educators. Older age, higher education and income, and HIV positive status were positively related to willingness to refer partners or relatives, while having health problems (mobility, usual care, pain/discomfort) was associated with lower likelihood of referring others or being a volunteer. Over 90% patients were willing to pay an average of US $17.9 for HTC service.ConclusionThe results highlighted the potential role of MMT patients as referrers to HTC and voluntary peer educators. Integrating HIV testing with MMT services and applying users’ fee are potential strategies to mobilize resources and encourage HIV testing among MMT patients and their partners. 相似文献
39.
Chapelle Frédérique Steiman Regine Seigle-Murandi Françoise Luu-Duc Cuong 《Applied microbiology and biotechnology》1986,23(6):430-433
Summary The ability of 610 strains of micromycetes to introduce a hydroxy-group into benzimidazole substrate has been investigated.
Among them, 232 micromycetes have been selected and cultivated in a liquid synthetic medium. Convenient hydroxylation of benzimidazole
was obtained with 78 fungi. Finally, 8 strains of micromycetes have been chosen for further investigation and optimization
of this bioconversion. 相似文献
40.
An unusual m-hydroxyacetophenone, named viscidone, and three new chroman-4-one derivatives were isolated from Chrysothamnus viscidiflorus ssp. lanceolatus, which also contained a known p-hydroxyacetophenone derivative. Their structures were determined by spectroscopic (1H and 13C NMR, UV, IR and MS) and chemical means. 相似文献