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31.
Rubinder K Chadha BS Singh N Saini HS Singh S 《Journal of industrial microbiology & biotechnology》2002,29(2):70-74
Thermomyces lanuginosus was subjected to three cycles of mutagenesis (UV/NTG) and a selection procedure to develop amylase-hyperproducing, catabolite-repression-resistant
and partially constitutive strains. One of the selected derepressed mutant strain III51, produced ∼7- and 3-fold higher specific activity of α-amylase (190 U/mg protein) and glucoamylase (105 U/mg protein), respectively,
compared to a wild-type parental strain. Further, the effect of production parameters on mutant strain III51 was studied using a Box–Behnken design. The regression models computed showed significantly high R
2 values of 96 and 97% for α-amylase and glucoamylase activities, respectively, indicating that they are appropriate for predicting
relationships between corn flour, soybean meal and pH with α-amylase and glucoamylase production. Journal of Industrial Microbiology & Biotechnology (2002) 29, 70–74 doi:10.1038/sj.jim.7000270
Received 05 July 2001/ Accepted in revised form 16 April 2002 相似文献
32.
Chintamani Sharma R Badran R Singhal V Saxena S Bansal A 《World journal of surgical oncology》2003,1(1):13
Background
Sweat gland adenocarcinoma is a rare malignancy with high metastatic potential seen more commonly in later years of life. Scalp is the most common site of occurrence and it usually spreads to lymph nodes. Liver, lung and bones are the distant sites of metastasis with fatal results. The differentiation between apocrine and eccrine metastatic sweat gland carcinoma is often difficult. The criteria's are inadequate to be of any practical utility. 相似文献33.
Anju Das K. M. Geetha Iswar Hazarika 《International journal of peptide research and therapeutics》2020,26(3):1211-1221
Pathogenesis of diabetes mellitus involves scores of different factors, out of which Glucagon like factor-1 (GLP-1) plays a foremost role. GLP-1 is a pepti 相似文献
34.
A mutation in the STN1 gene triggers an alternative lengthening of telomere-like runaway recombinational telomere elongation and rapid deletion in yeast 下载免费PDF全文
Some human cancer cells achieve immortalization by using a recombinational mechanism termed ALT (alternative lengthening of telomeres). A characteristic feature of ALT cells is the presence of extremely long and heterogeneous telomeres. The molecular mechanism triggering and maintaining this pathway is currently unknown. In Kluyveromyces lactis, we have identified a novel allele of the STN1 gene that produces a runaway ALT-like telomeric phenotype by recombination despite the presence of an active telomerase pathway. Additionally, stn1-M1 cells are synthetically lethal in combination with rad52 and display chronic growth and telomere capping defects including extensive 3' single-stranded telomere DNA and highly elevated subtelomere gene conversion. Strikingly, stn1-M1 cells undergo a very high rate of telomere rapid deletion (TRD) upon reintroduction of STN1. Our results suggest that the protein encoded by STN1, which protects the terminal 3' telomere DNA, can regulate both ALT and TRD. 相似文献
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A wild type Aspergillus terreus GD13 strain, chosen after extensive screening, was optimized for lovastatin production using statistical Box-Behnken design of experiments. The interactive effect of four process parameters, i.e. lactose and soybean meal, inoculum size (spore concentration) and age of the spore culture, on the production of lovastatin was evaluated employing response surface methodology (RSM). The model highlighted the positive effect of soybean meal concentration and inoculum level for achieving maximal level of lovastatin (1342 mg/l). The optimal fermentation conditions improved the lovastatin titre by 7.0-folds when compared to the titres obtained under unoptimized conditions. 相似文献
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Anju Rani Yogesh S. Souche Reeta Goel 《International biodeterioration & biodegradation》2009,63(1):62-66
A study was undertaken to examine the effects of the acidophilic strain 62BN (pH 5.5) and alkalophilic strain 97AN (pH 9.0) on remediation of cadmium and their subsequent effects on soybean (Glycine max var. PS-1347) in acidic and alkaline soils, respectively. The effect of cadmium on soybean plants was studied in acidic (pH 6.3 ± 0.2) and alkaline (8.5 ± 0.2) soil amended with 124 μM CdCl2 concentration, respectively, and the cadmium toxicity was evident from stunted growth, poor rooting, and cadmium accumulation in each case. Furthermore, 16S ribosomal DNA (rDNA) sequencing identified 62BN as a Pseudomonas putida strain and 97AN as a Pseudomonas monteilli strain. In situ studies showed that on seed bacterization, both the P. putida 62BN strain and P. monteilli 97AN strain were able to enhance plant growth in terms of agronomical parameters, in the presence of cadmium in acidic and alkaline soils, respectively. Apart from this, strain 62BN and 97AN reduced cadmium concentration in plant and soil significantly (p < 0.05) in their respective soil types. Further comparative analysis revealed that P. putida 62BN was more effective than P. monteilli 97AN strain in remediation of cadmium. The bacterial strains offer promise as inoculants to improve the growth of plants in the presence of toxic Cd concentrations in the environment with their optimum pH. 相似文献
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Thanemozhi G Natarajan Bhaskar V Kallakury Christine E Sheehan Margaret B Bartlett Natarajan Ganesan Anju Preet Jeffrey S Ross Kevin T FitzGerald 《Cancer cell international》2010,10(1):13