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71.
K. Sapna P. P. Manzur Ali K. R. Rekha Mol Sarita G. Bhat M. Chandrasekaran K. K. Elyas 《Biotechnology letters》2017,39(12):1911-1916
Objectives
An extracellular protease inhibitor (BTPI-301) of trypsin was purified and characterized from an isolate of Pseudomonas mendocina.Results
BTPI-301was purified to homogeneity by (NH4)2SO4, precipitation, DEAE Sepharose and CNBr-activated Sepharose chromatography. Homogeneity was proved by native PAGE and SDS-PAGE. The intact molecular mass was 11567 Da by MALDI-TOF analysis. BTPI-301was a competitive inhibitor with a Ki of 3.5 × 10?10 M. It was stable and active at pH 4–12 and also at 4–90 °C for 1 h. Peptide mass fingerprinting by MALDI revealed that the BTPI-301 is a new inhibitor not reported so far with protease inhibitory activity. The pI of the inhibitor was 3.8. The stoichiometry of trypsin-BTPI-301 interaction is 1:1. The inhibitor was specific towards trypsin.Conclusion
A pH tolerant and thermostable protease inhibitor BTPI-301 active against trypsin was purified and characterized from P. mendocina that could be developed and used as biopreservative as well as biocontrol agent.72.
In immunogold double-labeling of pea leaf thin sections with antibodies raised against ferredoxin-NADP reductase (EC 1.18.1.2, FNR) and antibodies directed against the A or B subunits of the NADP-linked glyceraldehyde-3-P dehydrogenase (GAPD) (EC 1.2.1.13), many small and large gold particles were found together over the chloroplasts. Nearest neighbor analysis of the distribution of the gold particles indicates that FNR and the NADP-linked GAPD are co-localized, in situ. This suggests that FNR might carry FADH2 or NADPH from the thylakoid membrane to GAPD, or that ferredoxin might carry electrons to FNR co-localized with GAPD in the stroma. Crystal structures of the spinach enzymes are available. When they are docked computationally, the proteins appear, as modeled, to be able to form at least two different complexes. One involves a single GAPD monomer and an FNR monomer (or dimer). The amino acid residues located at the putative interface are highly conserved on the chloroplastic forms of both enzymes. The other potential complex involves the GAPD A2B2 tetramer and an FNR monomer (or dimer). The interface residues are conserved in this model as well. Ferredoxin is able to interact with FNR in either complex. 相似文献
73.
Selvin J Shanmugha Priya S Seghal Kiran G Thangavelu T Sapna Bai N 《Microbiological research》2009,164(3):352-363
Sponges invariably filter a large volume of seawater and potentially accumulate heavy metals and other contaminants from the environment. Sponges, being sessile marine invertebrates and modular in body organization, can live many years in the same location and therefore have the capability to accumulate anthropogenic pollutants such as metals over a long period. Almost all marine sponges harbor large number of microorganisms within their tissues where they reside in the extra- and intra-cellular spaces. Bacteria in seawater have already been established as biological indicators of contamination. The present study was intended to find out the heavy metal resistance pattern of sponge-associated bacteria so as to develop suitable biological indicators. The bacteria associated with a marine sponge Fasciospongia cavernosa were evaluated as potential indicator organisms. The associated bacteria including Streptomyces sp. (MSI01), Salinobacter sp. (MSI06), Roseobacter sp. (MSI09), Pseudomonas sp. (MSI016), Vibrio sp. (MSI23), Micromonospora sp. (MSI28), Saccharomonospora sp. (MSI36) and Alteromonas sp. (MSI42) showed resistance against tested heavy metals. Based on the present findings, Cd and Hg emerged as the highly resistant heavy metal pollutants in the Gulf of Mannar biosphere reserve. Plasmids in varied numbers and molecular weights were found in all the isolates. Particularly the isolates MSI01 and MSI36 harbored as many as three plasmids each. The results envisaged that the plasmids might have carried the resistance factor. No correlation was observed in number of plasmids and level of resistance. The literature evidenced that the sponge-associated bacteria were seldom exploited for pollution monitoring though they have been extensively used for bioprospecting. In this background, the present findings come up with a new insight into the development of indicator models. 相似文献
74.
Harshita Negi Anil Kapri M.G.H. Zaidi Alok Satlewal Reeta Goel 《International biodeterioration & biodegradation》2009,63(5):553-558
A total of six bacterial isolates were developed into two consortia and tested for utilization of epoxy silicone blends (ESBs; % w/w: 3.0) and epoxy as the sole carbon source. In-vitro biodegradation studies in minimal broth revealed that higher biomass and more sustained growth of consortia were obtained in the presence of epoxy and/or ESBs when these were incubated under aerobic conditions for 15 days. Treated samples were analyzed by Fourier transform infrared spectroscopy (FTIR) and simultaneous thermogravimetric–differential thermogravimetry–differential thermal analysis (TG–DTG–DTA), which indicated the breakage and formation of bonds in the polymer backbone. Moreover, a weight loss of 34.17 and 36.9% was found in epoxy and ESBs, respectively after 15 days of treatment with consortium-1. Further, in-vitro growth statistics study revealed more CFU count at mid-logarithmic phase in the presence of epoxy/ESBs unlikely to the absence of the polymers. However, the generation time was not affected. In the present study, consortium-1, comprising of Microbacterium sp., Pseudomonas putida and Bacterium Te 68R showed better biodegradation in comparison to consortium-2, wherein, P. putida and Pseudomonas aeruginosa were present. Overall, these results suggest that epoxy/ESBs polymers could be degraded by a biologically mediated process if a suitable consortium is used. 相似文献
75.
Various parameters such as solvent selection, concentration, soaking time, and temperature were tested in a single bioreactor
in order to determine optimum extraction conditions of glucoamylase, when produced simultaneously with protease by Aspergillus awamari nakazawa MTCC 6652. Optimum conditions were achieved in a 10% glycerol solution soaked for 2 h at 40°C, followed by concentration
of extracted glucoamylase (9,157 U/gds) by acetone precipitation (1:2, v/v), which yielded 51.9% recovery. Ion exchange chromatography
and gel filtration showed specific activities of 270.5 and 337.5 U/mg, respectively, while SDS-PAGE and zymogram analysis
of glucoamylase indicated the presence of three starch-hydrolyzing isoforms with molecular weights of approximately 109.6,
87.1, and 59.4 kDa, respectively 相似文献
76.
Identification, characterization and utilization of unigene derived microsatellite markers in tea (Camellia sinensis L.) 总被引:1,自引:0,他引:1
Ram Kumar Sharma Pankaj Bhardwaj Rinu Negi Trilochan Mohapatra Paramvir Singh Ahuja 《BMC plant biology》2009,9(1):1-24
Background
Despite great advances in genomic technology observed in several crop species, the availability of molecular tools such as microsatellite markers has been limited in tea (Camellia sinensis L.). The development of microsatellite markers will have a major impact on genetic analysis, gene mapping and marker assisted breeding. Unigene derived microsatellite (UGMS) markers identified from publicly available sequence database have the advantage of assaying variation in the expressed component of the genome with unique identity and position. Therefore, they can serve as efficient and cost effective alternative markers in such species.Results
Considering the multiple advantages of UGMS markers, 1,223 unigenes were predicted from 2,181 expressed sequence tags (ESTs) of tea (Camellia sinensis L.). A total of 109 (8.9%) unigenes containing 120 SSRs were identified. SSR abundance was one in every 3.55 kb of EST sequences. The microsatellites mainly comprised of di (50.8%), tri (30.8%), tetra (6.6%), penta (7.5%) and few hexa (4.1%) nucleotide repeats. Among the dinucleotide repeats, (GA)n.(TC)n were most abundant (83.6%). Ninety six primer pairs could be designed form 83.5% of SSR containing unigenes. Of these, 61 (63.5%) primer pairs were experimentally validated and used to investigate the genetic diversity among the 34 accessions of different Camellia spp. Fifty one primer pairs (83.6%) were successfully cross transferred to the related species at various levels. Functional annotation of the unigenes containing SSRs was done through gene ontology (GO) characterization. Thirty six (60%) of them revealed significant sequence similarity with the known/putative proteins of Arabidopsis thaliana. Polymorphism information content (PIC) ranged from 0.018 to 0.972 with a mean value of 0.497. The average heterozygosity expected (H E ) and observed (H o ) obtained was 0.654 and 0.413 respectively, thereby suggesting highly heterogeneous nature of tea. Further, test for IAM and SMM models for the UGMS loci showed excess heterozygosity and did not show any bottleneck operating in the tea population.Conclusion
UGMS markers identified and characterized in this study provided insight about the abundance and distribution of SSR in the expressed genome of C. sinensis. The identification and validation of 61 new UGMS markers will not only help in intra and inter specific genetic diversity assessment but also be enriching limited microsatellite markers resource in tea. Further, the use of these markers would reduce the cost and facilitate the gene mapping and marker-aided selection in tea. Since, 36 of these UGMS markers correspond to the Arabidopsis protein sequence data with known functions will offer the opportunity to investigate the consequences of SSR polymorphism on gene functions. 相似文献77.
Srivastava V Saxena HO Shanker K Kumar JK Luqman S Gupta MM Khanuja SP Negi AS 《Bioorganic & medicinal chemistry letters》2006,16(17):4603-4608
Gallic acid, one of the most abundant plant phenolic acids, has been modified to cathepsin D protease inhibitors. The strategy of modification was proposed basing on some previously reported structure and activity relationship (SAR) studies. The synthesized naphthophenone fatty acid amide derivatives have been evaluated for in vitro cathepsin D inhibition activity. Two of them have shown significant inhibition activity with IC(50) values of 0.06 and 0.14 microM, respectively, as compared against pepstatin (0.0023 microM), the most potent inhibitor known so far. The study revealed that such attempts on gallic acid based pharmacophores might result in potent inhibitors of cathepsin D. 相似文献
78.
79.
The Cys(2)His(2)-type zinc finger is a common DNA binding motif that is widely used in the design of artificial zinc finger proteins. In almost all Cys(2)His(2)-type zinc fingers, position 4 of the α-helical DNA-recognition site is occupied by a Leu residue involved in formation of the minimal hydrophobic core. However, the third zinc finger domain of native Zif268 contains an Arg residue instead of the conserved Leu. Our aim in the present study was to clarify the role of this Arg in the formation of a stable domain structure and in DNA binding by substituting it with a Lys, Leu, or Hgn, which have different terminal side-chain structures. Assessed were the metal binding properties, peptide conformations, and DNA-binding abilities of the mutants. All three mutant finger 3 peptides exhibited conformations and thermal stabilities similar to the wild-type peptide. In DNA-binding assays, the Lys mutant bound to target DNA, though its affinity was lower than that of the wild-type peptide. On the other hand, the Leu and Hgn mutants had no ability to bind DNA, despite the similarity in their secondary structures to the wild-type. Our results demonstrate that, as with the Leu residue, the aliphatic carbon side chain of this Arg residue plays a key role in the formation of a stable zinc finger domain, and its terminal guanidinium group appears to be essential for DNA binding mediated through both electrostatic interaction and hydrogen bonding with DNA phosphate backbone. 相似文献
80.
Reichard GA Grice CA Shih NY Spitler J Majmundar S Wang SD Paliwal S Anthes JC Piwinski JJ 《Bioorganic & medicinal chemistry letters》2002,12(17):2355-2358
By employing a stereosimplification approach, a thorough SAR exploration of the piperidine region of Sch 206272 was possible through a practical and efficient synthesis of substituted cyclic ureas. This SAR study led to the identification of a benzimidazolinone series of compounds which display single digit nanomolar NK(1)/NK(2) affinity and near micromolar binding for the NK(3) receptor. 相似文献