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21.
To find out the genetic diversity of Indian Foc isolates of banana, a total of 107 isolates of Fusarium which includes 98 Foc isolates obtained from different banana growing regions of India and seven Foc isolates belong to all known VCGs obtained from Australia and two non-pathogenic Fusarium oxysporum (npFo) isolates were subjected to ISSR analysis. In the initial screening of ISSR primers, out of 34, 10 primers which generated more polymorphic bands were selected for further analysis. The Phylogenetic analysis carried out based on the fingerprints obtained through ISSR analysis indicated the presence of wide genetic diversity among the Foc isolates of India and also its polyphyletic nature. Totally, seven different clusters were obtained and these clusters differentiated the Foc isolates of India based on the races/VCGs. Besides, the cluster analysis clearly distinguished the freshly emerged Foc strain obtained from cv. Grand Naine (Cavendish-AAA) and Poovan (Mysore-AAB) from the other Foc isolates. The non-pathogenic F. oxysporum isolates which have been included for comparison purpose also clustered separately. All these above said findings indicates for the first time the discriminatory power of ISSR to clearly distinguish and separate the Foc isolates according to its race/VCGs and also its virulence. This study would be useful not only to design and develop effective management strategies but also useful for quarantine purposes. 相似文献
22.
Daser A Thangavelu M Pannell R Forster A Sparrow L Chung G Dear PH Rabbitts TH 《Nature methods》2006,3(6):447-453
Human cancers and some congenital traits are characterized by cytogenetic aberrations including translocations, amplifications, duplications or deletions that can involve gain or loss of genetic material. We have developed a simple method to precisely delineate such regions with known or cryptic genomic alterations. Molecular copy-number counting (MCC) uses PCR to interrogate miniscule amounts of genomic DNA and allows progressive delineation of DNA content to within a few hundred base pairs of a genomic alteration. As an example, we have located the junctions of a recurrent nonreciprocal translocation between chromosomes 3 and 5 in human renal cell carcinoma, facilitating cloning of the breakpoint without recourse to genomic libraries. The analysis also revealed additional cryptic chromosomal changes close to the translocation junction. MCC is a fast and flexible method for characterizing a wide range of chromosomal aberrations. 相似文献
23.
Mannazzu I Simonetti E Marinangeli P Guerra E Budroni M Thangavelu M Bowen S Wheals A Clementi F 《Applied and environmental microbiology》2002,68(11):5437-5444
The SED1 gene (YDR077W), coding for the major cell wall glycoprotein of Saccharomyces cerevisiae stationary-phase cells, contains two blocks of tandem repeat units located within two distinct regions of the nucleotide sequence. A PCR survey of the SED1 open reading frames (ORFs) of 186 previously uncharacterized grape must isolates of S. cerevisiae yielded 13 PCR profiles arising from different combinations of seven SED1 length variants in individuals homozygous or heterozygous for the gene. Comparison of the nucleotide sequences of a group of representatives of each of the seven length variants with those of S288C and the type strain, CBS1171, unequivocally identified them as SED1 alleles and provided evidence for the presence of two minisatellite-like sequences, variable in length, within the ORF of an S. cerevisiae gene. The segregation analyses of the SED1 length variants and other genetic markers in 13 isolates representative of each PCR profile suggested that molecular mechanisms involved in minisatellite expansion and contraction may be responsible for SED1 heterozygosities within a population of homothallic must isolates of S. cerevisiae. 相似文献
24.
Ultrasensitive electrochemical immunosensing using magnetic beads and gold nanocatalysts 总被引:1,自引:0,他引:1
In the current study, we developed a nanocatalyst-based electrochemical immunoassay using magnetic beads (MBs) and gold nanocatalysts (AuNs). The MBs conjugated with IgG allow easy separation of target proteins and rapid immunosensing reaction, and the AuNs conjugated with IgG amplifies electroactive species via catalytic reaction of AuNs. An antimouse IgG-MB conjugate and an antimouse IgG-AuN conjugate sandwich a target mouse IgG with low nonspecific binding. Thus formed immunosensing complex is strongly attracted to an indium tin oxide (ITO) electrode modified with partially ferrocenyl-tethered dendrimers (Fc-Ds) by using an external magnet. The AuN of the immunosensing complex produces p-aminophenol from p-nitrophenol by catalytic reduction in the presence of NaBH(4), and the generated p-aminophenol is electrooxidized at the Fc-D-modified ITO electrode. The oxidized product, p-quinone imine, is reduced back to p-aminophenol by NaBH(4) and then re-electrooxidized at the electrode. This redox cycling greatly amplifies the electrochemical signal. Moreover, the Fc-D-modified ITO electrode exhibits a low background current. Accordingly, the high signal-to-background ratio allows an extremely low detection limit of 1 fg/mL (7 aM) in cyclic voltammetric experiments and, importantly, 100 ag/mL (0.7 aM) in differential pulse voltammetric experiments. 相似文献
25.
Optimization of extracellular thermotolerant alkaline protease produced by marine <Emphasis Type="Italic">Roseobacter</Emphasis> sp. (MMD040) 总被引:1,自引:1,他引:0
Shanmughapriya S Krishnaveni J Selvin J Gandhimathi R Arunkumar M Thangavelu T Kiran GS Natarajaseenivasan K 《Bioprocess and biosystems engineering》2008,31(5):427-433
Marine endosymbiontic Roseobacter sp. (MMD040), which produced high yields of protease, was isolated from marine sponge Fasciospongia cavernosa, collected from the peninsular coast of India. Maximum production of enzyme was obtained in Luria-Bertani broth. Catabolite repression was observed when the medium was supplemented with readily available carbon sources. The optimum temperature and pH for the enzyme production was 37 degrees C and 7.0, respectively. The enzyme exhibited maximum activity in pH range of 6-9 with an optimum pH of 8.0 and retained nearly 92.5% activity at pH 9.0. The enzyme was stable at 40 degrees C and showed 89% activity at 50 degrees C. Based on the present findings, the enzyme was characterized as thermotolerant alkaline protease, which can be developed for industrial applications. 相似文献
26.
27.
Mustapha Aitchitt Charles C. Ainsworth Madan Thangavelu 《Plant Molecular Biology Reporter》1993,11(4):317-319
A method is presented for the rapid isolation of high-molecular-weight DNA from mature leaves of date palm (Phoenix dactylifera L.), using a CTAB-based buffer. The method yields up to 800 μg of DNA from 1 g of leaf tissues. The procedure was also suitable
for DNA extraction from callus or buds from tissue culture. The DNA obtained through this method was a good substrate for
at least seventeen restriction endonucleases. This method was also used to extract DNA from mature leaves of coconut and may
be applicable to other species of palms. 相似文献
28.
A rapid protocol for somatic embryogenesis from immature leaflets of groundnut (Arachis hypogaea L.)
P. Venkatachalam P. B. Kavi Kishor N. Geetha M. Thangavelu N. Jayabalan 《In vitro cellular & developmental biology. Plant》1999,35(5):409-412
Summary Plant regeneration via somatic embryogenesis was developed in two groundnut varieties. Somatic embryogenesis was induced from
immature leaflets on MS medium with different concentrations of the auxins 2,4-dichlorophenoxyacetic acid (2,4-D) or naphthaleneacetic
acid (NAA) in combination with 0.5 mg/l of the cytokinin BA. The highest frequency of somatic embryo formation occurred on
MS medium fortified with 20 mg 2,4-D per l. Of the two auxins tested individually 2,4-D was more effective for induction of
embryogenesis as well as production of embryos. Embryo development and maturation was achieved on MS medium supplemented with
N6-benzyladenine (BA) (0.5–2.0 mg/l) and 2,4-D (0.5 mg/l). Plant conversion frequency from somatic embryos was highest in presence
of 2.0 mg BA per l and 0.5 mg NAA per l. The frequency of embryogenesis and plant regeneration was higher in the VRI-2 cultivar
than in the other cultivar tested. Regenerated plants were transferred to soil, grown to maturity, and produced viable seeds. 相似文献
29.
Cannabidiol Activates Neuronal Precursor Genes in Human Gingival Mesenchymal Stromal Cells 下载免费PDF全文