共查询到20条相似文献，搜索用时 31 毫秒
1.
从浙江宁波雪菜上获得病毒分离物NBXC,病毒提纯后,电镜下可观察到大量长约740 nm的线形粒子。间接ELISA检测结果证实NBXC是芜菁花叶病毒(turnip mosaic virus,TuMV)的分离物。利用IC-RT-PCR对病毒分离物NBXC的CP和HC-Pro基因进行PCR扩增,分别得到约0.8 kb和1.4 kb的两条条带,与预期的TuMV CP和HC-Pro基因大小吻合。扩增产物克隆后进行序列测定,CP基因序列长度为864个核苷酸,编码288个氨基酸;HC-Pro基因序列长度为1374个核苷酸,编码458个氨基酸。NBXC的CP和HC-Pro基因与已报道的TuMV其他分离物的核苷酸序列同源率分别为90.0%～98.3%和82.2%～96.9%,氨基酸同源率分别为95.8%～99.3%和95.6%～99.3%。从CP和HC-Pro基因核苷酸序列同源性来看,NBXC与TuMV芸薹属分离物有更近的亲缘关系,而与萝卜属分离物亲缘关系较远。 相似文献
2.
P. Sharma M. Bose Isa Mohd S. Bagdi H. G. Raj 《Indian journal of clinical biochemistry : IJCB》2000,15(2):83-87
Genomic DNA from a clinical isolate ofMycobacterium avium-intracellulare complex was purified and cloned in PBR 322 at the tetracycline resistance site using Bam HI restriction enzyme. A 16 kb cloned
fragment was purified, radiolabeled and used as a probe. Genomic DNA isolated from nineteen MAC strains, threeM. tuberculosis strains and oneM. kansasii strain were digested with Eco RI restriction enzyme, Southern blotted and hybridized with the 16 kb cloned and labeled fragment.
Twelve MAC strains showed positive hybridization although five strains gave faint signals. Positive hybridization was noted
in two out of the threeM. tuberculosis strains, possibly due to shared DNA homology. No signal was received from the singleM. kansasii strain used in this study. 相似文献
3.
4.
Three different sets of primers were designed using FASTA homology search and PRIMERSELECT for the specific detection ofNeisseria gonorrhoeae using polymerase chain reaction (PCR). These primers amplified the highly conserved regions of genes for Open Reading Frame
(ORF), Outer Membrane Protein (OMP) and 23S rRNA sequences ofN. gonorrhoeae. Each of the PCR primer set was evaluated using the DNA samples isolated from eight different positive isolates ofN. gonorrhoeae cultured from urethral swabs of patients visiting Maulana Azad Medical College and Safdarjung Hospital. Amplification products
were analyzed on agarose gel electrophoresis. Two sets of PCR primers, designated as Ngu1/Ngu2 and Ngu5/Ngu6, specific for
ORF and OMP gene respectively, amplified four regions of the gene which may help to differentiate the various strains ofN. gonorrhoeae infecting indigenous population. In contrast, a single, specific PCR product of 650 bp was visualized on agarose gel with
primers Ngu3/Ngu4, amplifying the 23S rRNA gene. Under optimum conditions, as low as 25ng of DNA isolated from eight different
clinical strains ofN. gonorrhoeae could be detected by PCR using Ngu3/Ngu4 set of primers. Our results suggested that Ngu3/Ngu4 could serve as good primers
for the specific, reproducible and sensitive diagnosis ofNeisseria gonorrhoeae from clinical samples. 相似文献
5.
Boolean logic performs a logical operation on one or more logic input and produces a single logic output. Here, we describe a microfluidic DNA computing processor performing Boolean logic operations for gene expression analysis and gene drug synthesis. Multiple cancer-related genes were used as input molecules. Their expression levels were identified by interacting with the computing related DNA strands, which were designed according to the sequences of cancer-related genes and the suicide gene. When all the expressions of the cancer-related genes fit in with the diagnostic criteria, positive diagnosis would be confirmed and then a complete suicide gene (gene drug) could be synthesized as an output molecule. Microfluidic chip was employed as an effective platform to realize the computing process by integrating multistep biochemical reactions involving hybridization, displacement, denaturalization, and ligation. By combining the specific design of the computing related molecules and the integrated functions of the microfluidics, the microfluidic DNA computing processor is able to analyze the multiple gene expressions simultaneously and realize the corresponding gene drug synthesis with simplicity and fast speed, which demonstrates the potential of this platform for DNA computing in biomedical applications. 相似文献
6.
Suvidya H. Ranade Ashraf Hossani D. N. Deobagkar D. D. Deobagkar B. A. Chopade Pramod S. Khandekar 《Indian journal of clinical biochemistry : IJCB》2009,24(2):142-149
We report complete sequences of 2 genes of S.flexneri 1a an Indian isolate for the first time. Shigella is causative agent
of shigellosis or bacillary dysentery. Genomic library was constructed by shotgun approach. Sequencing was carried out using
Big Dye terminator chemistry using ABI 3730 48 capillary DNA analyzer. 170 recombinants were subjected to nucleotide sequencing.
Sequence data was analyzed, of these 2 clones showed presence of complete genes out of the total clones sequenced. Annotations
were done using various bioinformatics tools. Gene Sfo676 on contig SF21B11, 513 bp long codes for a protein 170 aa long with
molecular weight of 18836.5 daltons. The protein is 99 % identical to S. flexneri 2a 301 and not with any other strain of
Shigella. It has 7 different sites for phosphorylation, myristoylation and glycosylation. Predicted cellular localization
is cytoplasmic membrane. SF0368 is another full-length gene SF0368 on contig SF69C1 is a 312 nucleotide long. It is 103 aa
long with molecular weight 11394.0 daltons. Protein is 100% identical to S. flexneri 2a 301 and 99% with S. sonnei strain
046. The gene shows difference when compared with S.sonnei in mono and dinucleotide frequency as well as amino acid composition. 相似文献
7.
8.
D. Saravanakumar N. Elangeswaran S. Senthilkumar G. Vanaja S. Kamakshiammal C. Chandrasekar C. N. Deivanayagam Manjula Sritharan V. Sritharan 《Indian journal of clinical biochemistry : IJCB》2000,15(2):94-103
We have isolated and identified the biotype of environmental mycobacteria from the expectorate of leprosy patients, their
contacts, their drinking water supply and also from the sputa samples of tuberculosis patients. 78% of the isolates from lepromatous
leprosy patients and their contacts wereMycobacterium fortuitum- chelonae complex (MFC), 9%Mycobacterium avium complex (MAC), 9%Mycobacterium scrofulaceum and 4% wereMycobacterium smegmatis. Among the isolates from tuberculosis patients 63% belonged toM. fortuitum- chelonae complex, 19% toM. avium complex, 12% toMycobacterium Kansasii and 6% toM. smegmatis. All the isolates were multi-drug resistant when tested for sensitivity total of 21 drugs. TheMycobacterium fortuitum-chelonae complex organisms from leprosy contacts were more sensitive to rifampicin than those isolated from lepromatous leprosy and
tuberculosis patients. Among 23 isolates from leprosy patients one isolate was resistant to 20 drugs, one isolate to 17 drugs
and another isolate was resistant to 13 drugs. Among the 18 isolates from drinking water supply six showed resistance to more
than 12 drugs. Polymerase Chain Reaction (PCR) and subsequent hybridisation with specific probes confirmed all the isolated
strains as nontuberculous mycobacteria (Using genus primers and probe sensitivity 100%) and none asM. tuberculosis, suggesting that PCR could be used to rapidly identify mycobacteria at the genus level and to rule out tuberculosis in leprosy
patients at an early stage to decide on appropriate course of therapy. 相似文献
9.
10.
Patra SK Jain A Sherwal BL Khanna A 《Indian journal of clinical biochemistry : IJCB》2010,25(3):315-318
To detect the site of mutation in RRDR of rpo B gene for rifampicin resistance in MDR-TB by DNA sequencing. 50 MDR-TB patients
were enrolled in our study after informed written consent. Mycobacterial DNA was extracted from sputum samples by Universal
Sample Processing (USP) method and RRDR of rpo B gene was amplified by PCR using primers RP4T and RP8T and then sequenced
by automated DNA sequencing. The nucleotide sequences of RRDR of rpo B gene were compared with the reference sequence. We
observed three different types of mutation in the RRDR of rpo B gene. The frequency of mutation in codon 531 (TCG → TTG),
526 (CAC → TAC) and 516 (GAC → GTC) are 60, 26.6 and 6.6% respectively. Of the total cases studied, 6.6% cases, although resistant
to rifampicin, did not show any mutation in the RRDR of rpo B gene. Codon 531 (TCG → TTG) is the most common site of mutation
in RRDR of rpo B gene for rifampicin resistance in MDR-pulmonary tuberculosis followed by codon 526 (CAC → TAC) and codon
516 (GAC → GTC). 相似文献
11.
Farrokhi E Shayesteh F Asadi Mobarakeh S Roghani Dehkordi F Ghatreh Samani K Hashemzadeh Chaleshtori M 《Indian journal of clinical biochemistry : IJCB》2011,26(3):244-248
Familial hypercholesterolemia (FH) is an autosomal dominant disorder of lipoprotein metabolism caused mainly by mutations
in the low-density lipoprotein receptor (LDLR) and apolipoprotein B 100 (APOB) genes. Until now, the molecular basis of FH
has been demonstrated in detail in many populations, but there is still very limited Molecular data concerning FH in Iran.
The aim of this study was to characterize the LDLR and APOB gene mutations in an Iranian population. A total of 30 non-related
Iranian possible FH subjects were studied. Diagnosis of FH was based on the Dutch Lipid Clinic Network diagnostic criteria.
All samples were initially tested for three common APOB gene mutations including R3500Q, R3500 W and R3531C using PCR-RFLP
assay. Subsequently, promoter and coding region of the LDLR gene was screened by PCR-SSCP analysis and positive results were
confirmed by DNA sequencing. Four previously reported polymorphisms 1413G > A, 1725C > T, 1773T > C and 2140 + 5G > A were
found in ~17% (5/30) of population studied. Moreover, no variation was found in APOB gene. Our data indicated that LDLR and
APOB gene mutations have not contribution to possible FH in Iranian population studied here. However, we examined three common
APOB mutations and LDLR in only 30 patients, and to determine the role of these genes in developing FH in Iran, more FH samples
and populations needed to be investigated for the mutations of the related genes. 相似文献
12.
鱼类干扰素系统基因的克隆鉴定及其特征分析 总被引：2，自引：0，他引：2
干扰素 (IFN)系统是脊椎动物抵抗病毒入侵的第一道防御系统 .除了哺乳类 ,有关低等脊椎动物的IFN系统基因知之甚少 .在鱼类 ,近 40年来能证明IFN系统存在的证据主要有两个 :一是检测经病毒诱导后的多种鱼类机体和细胞 ,证明能产生类似哺乳类IFN的抗病毒活性物质 ;二是近年来 ,已经证明在少数几种鱼类中存在与哺乳类IFN系统基因Mx同源的基因 .以前的研究结果表明 ,紫外线灭活的草鱼出血病病毒 (GCHV)能够诱导鲤科鱼类培养细胞 ,如鲫鱼囊胚细胞 (CAB)产生类IFN活性物质 ,并建立宿主细胞的抗病毒状态 .为了揭示鱼类培养细胞抗病毒免疫的分子机制 ,首先建立了一个研究鱼类抗病毒免疫相关基因的细胞模型系统 ,通过用灭活GCHV诱导CABIFN并进行理化、生物学特性鉴定的基础上 ,成功建立了一个囊括鱼类细胞抗病毒基因在内的差减cDNA文库 .其次 ,筛选文库揭示了一批与哺乳类IFN系统基因同源以及找不到同源性的EST ,表达分析证实它们也是IFN刺激基因 .再次 ,根据哺乳类IFN系统研究的最新进展 ,从该细胞模型系统中克隆、鉴定了 1 9个IFN系统基因的全长cDNA序列 ,包括鲫鱼IFN基因 ,IFN信号传导通路基因STAT1 ,IFN诱导表达调控基因IRF7,IFN行使抗病毒作用的效应基因Mx1、Mx2、PKR、Viperin、IFI5 6,以及一些功能未知的 相似文献
13.
14.
15.
16.
Raúl J. Cano 《Endeavour》1996,20(4):162-167
Much of what we know about extinct organisms comes from traits that are not preserved in the fossil record. Until recently, morphological analysis was the only tool available for scientists to determine relationships for extinct fossil organisms. We now know that ‘ancient’ DNA can be preserved in the remains of extinct organisms. By targeting specific gene sequences, it may be possible to deduce biochemical characteristics and through sequence comparisons, to estimate the extent of evolutionary divergence. By comparing the amount and type of these changes, one could estimate how quickly some DNA ‘evolves’ relative to other segments, or which genes have the most flexibility or are more conserved over time. The compilation of these data would yield greater understanding of the physiology of extinct organisms and provide a much clearer picture of genetic change over time, and the mechanics behind ‘evolution’. 相似文献
17.
18.
Alja Videtic Paska Petra Hudler 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2015,25(2):161-176
Epigenetic mechanisms, such as DNA methylation, DNA hydroxymethylation, post-translational modifications (PTMs) of histone proteins affecting nucleosome remodelling, and regulation by small and large non-coding RNAs (ncRNAs) work in concert with cis and trans acting elements to drive appropriate gene expression. Advances in detection methods and development of dedicated platforms and methylation arrays resulted in an explosion of information on aberrantly methylated sequences linking deviations in epigenetic landscape with the initiation and progression of complex diseases. Here, we consider how DNA methylation changes in malignancies, such as breast, pancreatic, colorectal, and gastric cancer could be exploited for the purpose of developing specific diagnostic tools. DNA methylation changes can be applicable as biomarkers for detection of malignant disease in easily accessible tissues. Methylation signatures are already proving to be an important marker for determination of drug sensitivity. Even more, promoter methylation patterns of some genes, such as MGMT, SHOX2, and SEPT9, have already been translated into commercial clinical assays aiding in patient assessment as adjunct diagnostic tools. In conclusion, the changes in DNA methylation patterns in tumour cells are slowly gaining entrance into routine diagnostic tests as promising biomarkers and as potential therapeutic targets.Key words: biomarkers, CpG islands, DNA methylation, molecular diagnostics, epigenetics 相似文献
19.
拟南芥GH3基因家族启动子序列分析 总被引：1，自引：0，他引：1
GH3 基因家族是植物生长素早期响应基因家族之一.拟南芥 10个GH3 基因启动子序列分析表明:GH3 基因的转录起始位点一般在起始密码子上游65~145bp之内,TATA box大多分布在(-24)~(-40)bp区域.MDB和MatInspector分析显示,AtGH3 s基因的上游调控区域普遍存在组织和器官特异性表达元件、激素响应元件以及环境响应元件,表明GH3 基因的表达受到多因素调控;同时,基因芯片数据显示AuxREs对生长素的响应非常重要,但也可能存在其他的生长素响应元件. 相似文献