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971.
Porwal S Kumar T Lal S Rani A Kumar S Cheema S Purohit HJ Sharma R Singh Patel SK Kalia VC 《Bioresource technology》2008,99(13):5444-5451
Thirty five bacterial isolates from diverse environmental sources such as contaminated food, nitrogen rich soil, activated sludges from pesticide and oil refineries effluent treatment plants were found to belong to Bacillus, Bordetella, Enterobacter, Proteus, and Pseudomonas sp. on the basis of 16S rRNA gene sequence analysis. Under dark fermentative conditions, maximum hydrogen (H2) yields (mol/mol of glucose added) were recorded to be 0.68 with Enterobacter aerogenes EGU16 followed by 0.63 with Bacillus cereus EGU43 and Bacillus thuringiensis EGU45. H2 constituted 63–69% of the total biogas evolved. Out of these 35 microbes, 18 isolates had the ability to produce polyhydroxybutyrate (PHB), which varied up to 500 mg/l of medium, equivalent to a yield of 66.6%. The highest PHB yield was recorded with B. cereus strain EGU3. Nine strains had high hydrolytic activities (zone of hydrolysis): lipase (34–38 mm) – Bacillus sphaericus strains EGU385, EGU399 and EGU542; protease (56–62 mm) – Bacillus sp. strains EGU444, EGU447 and EGU445; amylase (23 mm) – B. thuringiensis EGU378, marine bacterium strain EGU409 and Pseudomonas sp. strain EGU448. These strains with high hydrolytic activities had relatively low H2 producing abilities in the range of 0.26–0.42 mol/mol of glucose added and only B. thuringiensis strain EGU378 had the ability to produce PHB. This is the first report among the non-photosynthetic microbes, where the same organism(s) – B. cereus strain EGU43 and B. thuringiensis strain EGU45, have been shown to produce H2 – 0.63 mol/mol of glucose added and PHB – 420–435 mg/l medium. 相似文献
972.
Kumar V Rani N Aggarwal P Sanna VK Singh AT Jaggi M Joshi N Sharma PK Irchhaiya R Burman AC 《Bioorganic & medicinal chemistry letters》2008,18(18):5058-5062
A new series of betulinic acid derivatives have been synthesized by introducing heterocyclic ring between C-2 and C-3 positions of betulinic acid. Further modifications were also carried out by reduction of C-20(29) unsaturated bond and substitution of C-28 carboxyl group by ester and amide linkage to enhance the selectivity. Compound 11 resulted in IC(50) of 2.44, 2.5, and 2.7 microg/ml on MIAPaCa, PA-1, and SW620 cancer cell lines, respectively. Compound 38 resulted in IC(50) of 0.67 microg/ml on MIAPaCa cell line. 相似文献
973.
Vibha Khandelwal Malavika Dadlanl P. C. Sharma Ashwani Pareek S. P. Sharma 《Journal of plant biochemistry and biotechnology.》2005,14(2):135-139
Molecular characterization of 32 Indian rice varieties of different agro-climatic zones resulted in mean heterozygosity value of 0.622, 0.819 and 0.890 over polymorphic loci and marker index value of 1.00, 6.75 and 4.16, respectively for RAPD, ISSR and STMS primers. The three marker systems resulted in 201 polymorphic bands (94.36%) out of a total of 213 bands. The probability of a chance identical match between two varieties was very low (2.08x1010) in combined molecular marker analysis as compared to individual marker system (RAPD, 7.5 x 10-4; ISSR, 1.5 x 10-3 and STMS, 3.9 x 10-6). The combined average genetic similarity for molecular markers and coefficient of parentage (COP) across all 496 pairwise combinations revealed a non-significant relationship (r = 0.215). 相似文献
974.
S. Kumar J. K. Kanwar D. R. Sharma 《Journal of plant biochemistry and biotechnology.》2004,13(1):73-75
Regeneration of adventitious shoots from leaf and petiole pieces of Gerbera jamesonii has been obtained on Murashige and Skoog (MS) medium supplemented with different concentrations of auxins and cytokinins. About 75’77 per cent of the calli from both types of the explants produced 12’15 shoots per callus with 3 mg l?1 SAP. Auxins and kinetin, separately failed to produce shoots. The shoots regenerated on the callus induction medium (elM). The regenerated shoots multiplied with 1 mg l?1 SAP, were rooted on MS medium containing 1mg l-1 BAP + 0.1 mg l-1 IAA. The plants obtained were transferred to pots and acclimatized with 60’70 per cent success. 相似文献
975.
Pratibha Misra S. K. Datta J. K. Johri H. B. Singh A. Srivastava 《Journal of plant biochemistry and biotechnology.》2004,13(2):161-164
A protocol for large-scale propagation of Piper betle cvs Desawari and Desi Bangla was developed through axillary shoot proliferation. Due to systemic infection as well as high phenol content the crop was very difficult to establish in aseptic condition. But a mixture of 5 mg l?1 each of chloramphenicol and oxytetracyclin and 100 mg l?1 each of citric acid and ascorbic acid used in MS medium for 2 days helped in establishment. After 48 h, the explants were transferred to the antibiotic free medium having PVP and ascorbic acid (100 mg l?1 each), citric acid (50 mg l?1), and glutathione (20 mg l?1). Regular subculturing of the explants into liquid medium, use of antioxidants and incubation of the cultures in the dark for initial 7–10 days played a crucial role for keeping them fresh and green. Maximum numbers of axillary shoots were obtained with 2 mg l?1 BA and 0.2 mg l?1 NAA as growth supplements. The plants were rooted in 0.25 mg l?1 IBA and hardened in the soil. Phenolic compound analysis showed almost the same results in tissue-raised and in vivo grown plants in Desawari. 相似文献
976.
Objective: To identify research published on obesity in Canada, to explore the range of areas studied, and to identify gaps and areas that merit future research attention. Research Methods and Procedures: Medline and International Pharmaceutical Abstracts databases were searched from 1970 onwards. Original articles were identified and categorized by areas of interest. Results: A total of 1186 relevant articles were identified: 17, 136, 687, and 346 articles during the 1970s, 1980s, 1990s, and 2000 to 2003, respectively. Of the articles, 816 were considered original studies and accepted for this analysis. Twelve research areas were identified: basic science involving animal experiments (29%), human experiments (16%), populations surveys (14%), obesity‐related comorbidities (13%), diagnostic/surgical issues (11%), nonpharmacological approaches (7%), drug‐related issues (4%), anthropometrics (2%), impact of weight loss (2%), cost/healthcare use (1%), attitudes/perceptions (0.9%), and models/procedures (0.5%). Two‐thirds of all research was conducted in Quebec (34%) and Ontario (33%). Discussion: Given the multifactorial nature of obesity, Canadian obesity research covers a broad range of areas with a predominance of basic science but lesser emphasis on community and primary care studies. Furthermore, there was a paucity of research on either clinical management of medical conditions in obese patients or clinical aspects that go beyond weight loss. Thus, although Canada appears well represented in basic research, more attention to exploration of clinical issues and healthcare delivery for obese patients appears warranted. 相似文献
977.
D'Souza David R. Morgan Richard D. Parashar Vijay Capalash Neena Sharma Prince 《World journal of microbiology & biotechnology》2004,20(6):593-598
A thermophile, isolated from geothermal areas in the northern Himalayan region of India, was identified by partial 16S rDNA
sequence (GenBank accession # AF482430) analysis as Anoxybacillus flavithermus. The isolate produced BflI (REBASE # 4910), a Type II restriction endonuclease, which recognized the sequence 5′-CCNNNNN/NNGG-3′ and was the isoschizomer
of BsiYI. The enzyme was purified to homogeneity by passing through Cibacron Blue F3GA agarose, DEAE-cellulose, heparin-agarose
and MonoQ FPLC. The purified enzyme (MW 36 kDa) worked best at 60 °C in Promega's buffer C and preferentially required Co++(0.4 mM) as cofactor followed by Mg++(10 mM) and Mn++(1 mM). The enzyme showed high specific activity and worked in the presence of high concentrations of β-mercaptoethanol (200
mM), Triton-X-100 (25%), urea (30%), formamide (6%) and guanidine (40 mM) and showed no star activity in the presence of 40%
glycerol. In the absence of any stabilizing agent, BflI retained t
1/2 for at least 96 h at 37 °C, 6 h at 60 °C and 6 months at 4 °C. N-terminal sequencing showed that its first 10 amino acid
residues were DFHEDKTIAR.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
978.
Hejtmancik JF Jiao X Li A Sergeev YV Ding X Sharma AK Chan CC Medina I Edwards AO 《American journal of human genetics》2008,82(1):174-180
Snowflake vitreoretinal degeneration (SVD, MIM 193230) is a developmental and progressive hereditary eye disorder that affects multiple tissues within the eye. Diagnostic features of SVD include fibrillar degeneration of the vitreous humor, early-onset cataract, minute crystalline deposits in the neurosensory retina, and retinal detachment. A genome-wide scan previously localized the genetic locus for SVD to a 20 Mb region flanked by D2S2158 and D2S2202. This region contains 59 genes, of which 20 were sequenced, disclosing a heterozygous mutation (484C > T, R162W) in KCNJ13, member 13 of subfamily J of the potassium inwardly rectifying channel family in all affected individuals. The mutation in KCNJ13, the gene encoding Kir7.1, was not present in unaffected family members and 210 control individuals. Kir7.1 localized to human retina and retinal pigment epithelium and was especially prevalent in the internal limiting membrane adjacent to the vitreous body. Molecular modeling of this mutation predicted disruption of the structure of the potassium channel in the closed state located immediately adjacent to the cell-membrane inner boundary. Functionally, unlike wild-type Kir7.1 whose overexpression in CHO-K1 cells line produces highly selective potassium current, overexpression of R162W mutant Kir7.1 produces a nonselective cation current that depolarizes transfected cells and increases their fragility. These results indicate that the KCNJ13 R162W mutation can cause SVD and further show that vitreoretinal degeneration can arise through mutations in genes whose products are not structural components of the vitreous. 相似文献
979.
Mechanism of inhibition of matrix metalloproteinase-9 induction by NO in vascular smooth muscle cells. 总被引:4,自引:0,他引:4
Vascular smooth muscle (VSM) cell migration is a critical step in the development of a neointima after angioplasty. Matrix metalloproteinases (MMPs) degrade the basement membrane and extracellular matrix, facilitating VSM cell migration. Recently, we demonstrated that nitric oxide (NO) inhibits interleukin-1 beta (IL-1 beta)-stimulated MMP-9 induction in rat aortic VSM cells. In this study, we examined the hypothesis that NO inhibits MMP-9 induction by attenuating superoxide generation and extracellular signal-regulated kinase (ERK) activation. Stimulation of VSM cells with IL-1 beta significantly (P < 0.05) increased superoxide production, ERK activation, and MMP-9 induction. Pretreatment of VSM cells with the NO donor DETA NONOate significantly (P < 0.05) decreased IL-1 beta-stimulated superoxide generation. In addition, pretreatment of VSM cells with a specific ERK pathway inhibitor, PD-98059, or DETA NONOate inhibited IL-1 beta-stimulated ERK activation and MMP-9 induction. Direct exposure of VSM cells to increased superoxide levels by treatment with xanthine/xanthine oxidase increased ERK activation and MMP-9 induction, whereas pretreatment of cells with PD-98059 significantly (P < 0.05) inhibited xanthine/xanthine oxidase-stimulated ERK activation and MMP-9 induction. We conclude that NO inhibits IL-1 beta-stimulated MMP-9 induction by inhibiting superoxide generation and subsequent ERK activation. 相似文献
980.
Transcription of the gene mediating methicillin resistance in Staphylococcus aureus (mecA) is corepressed but not coinduced by cognate mecA and beta-lactamase regulators. 总被引:1,自引:0,他引:1 下载免费PDF全文
Tanya K. McKinney Vijay K. Sharma William A. Craig Gordon L. Archer 《Journal of bacteriology》2001,183(23):6862-6868