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1.
A simple and reproducible procedure for the recovery of plasmid DNA is described. The method was standardised for the purification of plasmids from Gluconobacter oxydans ATCC9937. The protocol is based on the use of glass microfibre filter paper for entrapment of DNA and its subsequent recovery by an elution buffer. The method precludes the use of phenol and butanol for the removal of proteins and ethidium bromide respectively, therefore, making the procedure inexpensive and gentle. 相似文献
2.
S. Koul V. Verma S. Johri G. N. Qazi 《World journal of microbiology & biotechnology》1995,11(2):234-235
Erwinia herbicola (ATCC 21998), a facultative anaerobe, has two plasmids: pVQ1 and pVQ2. Curing with mitomycin C indicated that pVQ2 was cryptic but pVQ1, a 7.4-kb plasmid, bears a 4.3SacI fragment which strongly hybridized to the C-terminal region of the glucose dehydrogenase gene ofAcinetobacter calcoaceticus. A restriction map of plasmid pVQ1 is presented.The authors are with the Department of Biotechnology, Regional Research Laboratory, Canal Road, Jammu Tawi-180 001, India; 相似文献
3.
Body weight, testicle size and peripheral testosterone concentrations were measured in 35 water buffalo bulls at 5, 15, 17, 21, 25 and 38 months of age. These parameters were studied in all animals during the same month (October), so the changes due to age were independent of changes in photoperiod and temperature. Body weight increased linearly with age. The testicular size measured in terms of scrotal circumference as related to age, showed a curvilinear increase; the average rate of testicular growth was maximum between 15 and 25 months. Plasma testosterone levels were low between 5 and 21 months. A significant rise in plasma concentration of testosterone was observed at 25 months reaching peak levels at 38 months. The mean age of sexually mature bulls at the time of first ejaculation of semen with motile sperm, was 24.9±0.9 months (n=9). It has been concluded that in the Nili-Ravi buffalo bulls the sexually quiescent period (prepubertal) extends up to 15 months of age and sexual maturation as indicated by the presence of motile sperm in the ejaculate is attained at about 25 months. 相似文献
4.
Molecular cloning of enantioselective ester hydrolase from Bacillus pumilus DBRL-191 总被引:1,自引:0,他引:1
Rasool S Johri S Riyaz-ul-Hassan S Maqbool QU Verma V Koul S Taneja SC Qazi GN 《FEMS microbiology letters》2005,249(1):113-120
A gene from Bacillus pumilus expressed under its native promoter was cloned in Escherichia coli. Recombinant B. pumilus esterase (BPE) affects the kinetic resolution of racemic mixtures such as unsubstituted and substituted 1-(phenyl)ethanols (E approximately 33-103), ethyl 3-hydroxy-3-phenylpropanoate (E approximately 45-71), trans-4-fluorophenyl-3-hydroxymethyl-N-methylpiperidine (E approximately 10-13) and ethyl 2-hydroxy-4-phenylbutyrate (E approximately 7). The enzyme is composed of a 34-amino acid signal peptide and a 181-amino acid mature protein corresponding to a molecular weight of approximately 19.2kD and pI approximately 9.4. 3-D the structural model of the enzyme built by homology modelling using the atomic coordinates from the crystal structure of B. subtilis lipase (LipA) showed a compact minimal alpha/beta hydrolase fold. 相似文献
5.
6.
S Johri A Bhat S Sayed A Nargotra A Jain GN Qazi 《World journal of microbiology & biotechnology》2012,28(1):193-203
Thermophilic Bacillus circulans IIIB153 isolated from hot springs of North West Himalayas, India, produced an extracellular lipase, which exhibited significant
biofilm disruption property on the static biofilm disruption model with a single species of Actinomyces
viscosous. The gene encoding the lipase was cloned and overexpressed in Escherichia coli. Recombinant Bacillus circulans lipase (BCL), a monomer with molecular mass of 43 kDa also exhibited significant biofilm disruption activity. The enzyme
was optimally active at 60°C, pH 8.5 and retained >70% of its original activity after 1 h incubation at 60°C. 3D structure
of BCL developed by homology modeling showed a typical α/β hydrolase fold, a characteristic feature of lipolytic enzymes.
Comparison of thermostable BCL with mesostable lipase from Chromobacterium viscosum at the sequence and structure level showed distinct variations in the structural features, with the presence of a high content
of proline residues, aromatic amino acids and salt bridges. These features along with the presence of zinc-binding site observed
in BCL structure could have a potential role in thermal stability of the enzyme. 相似文献
7.
8.
Angiogenesis is the formation of new blood vessels from pre-existing vasculature. Pathologic angiogenesis in the eye can lead
to severe visual impairment. In our review, we discuss the roles of both pro-angiogenic and anti-angiogenic molecular players
in corneal angiogenesis, proliferative diabetic retinopathy, exudative macular degeneration and retinopathy of prematurity,
highlighting novel targets that have emerged over the past decade. 相似文献
9.
Abbu Zaid Firoz Mohammad Qazi Fariduddin 《Physiology and Molecular Biology of Plants》2020,26(1):25-39
Menthol mint (Mentha arvensis L.) cultivation is significantly affected by the heavy metals like cadmium (Cd) which also imposes severe health hazards. Two menthol mint cultivars namely Kosi and Kushal were evaluated under Cd stress conditions. Impact of plant growth regulators (PGRs) like salicylic acid (SA), gibberellic acid (GA3) and triacontanol (Tria) on Cd stress tolerance was assessed. Reduced growth, photosynthetic parameters, mineral nutrient concentration, and increased oxidative stress biomarkers like electrolyte leakage, malondialdehyde, and hydrogen peroxide contents were observed under Cd stress. Differential upregulation of proline content and antioxidant activities under Cd stress was observed in both the cultivars. Interestingly, low electrolyte leakage, lipid peroxidation, hydrogen peroxide and Cd concentration in leaves were observed in Kushal compared to Kosi. Among all the PGRs tested, SA proved to be the best in improving Cd-stress tolerance in both the cultivars but Kushal responded better than Kosi. 相似文献
10.