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861.
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864.
N. Annamalai R. Thavasi S. Vijayalakshmi T. Balasubramanian 《World journal of microbiology & biotechnology》2011,27(9):2111-2115
A novel thermostable, halostable carboxymethylcellulase (CMCase) from a marine bacterium Bacillus licheniformisAU01 was purified 10.4-fold with 18% yield with a specific activity of 88.43 U/mg and the molecular weight was estimated as
37 kDa. The enzyme was optimally active at pH 9–10 and temperature 50–60°C and it was most stable up to pH 12 and 20–30% of
NaCl concentration. The enzyme activity was reduced when treated with Hg2+, Fe2+ and EDTA and stimulated by Co2+, Mn2+, Mg2+ and Ca2+. Various cationic, anionic detergents and commercial detergents were not much affected CMCase activity. 相似文献
865.
Fredric A. Gorin T. M. Balasubramanian C. David Barry Garland R. Marshall 《Journal of cellular biochemistry》1978,9(1):27-39
The biologically relevant conformers of enkephalin predicted by solid state, solution state, and theoretical energy studies have been compared with the published structure-activity data on these compounds. No conformational technique proposes a model consistent with all the pharmacological data; the shortcomings of each approach are evaluated. An alternative approach, which correlates the structure-activity data of opiate compounds with that of the enkephalins, is described and shown to produce a model consistent with the available structure-activity data. 相似文献
866.
867.
Acetylcholinesterase was purified from the soluble supernatant of monkey (Macaca radiata) brain basal ganglia by a three-step affinity purification procedure. The purified enzyme showed two major protein bands corresponding to molecular weights of approximately 65 kDa and approximately 58 kDa which could be labelled by [3H]diisopropylfluorophosphate. When the purified enzyme was subjected to limited trypsin digestion followed by gel filtration on Sephadex G-75 or Sephadex G-25 column, a peptide fragment of molecular weight approximately 300 Da having a weak acetylthiocholine hydrolysing activity was isolated. The amino acid sequence analysis of this peptide showed a sequence of Gly-Pro-Ser. When the [3H]DFP labelled enzyme was subjected to limited trypsin digestion and Sephadex G-75 column chromatography, a labelled peptide corresponding to approximately 430 Da was isolated. The kinetics, inhibition characteristics and binding characteristics to lectins of this peptide were compared with the parent enzyme. A synthetic peptide of sequence Gly-Pro-Ser was also found to exhibit acetylthiocholine hydrolysing activity. The kinetics and inhibition characteristics of the synthetic peptide were similar to those of the peptide derived from the purified acetylcholinesterase, except that the synthetic peptide was more specific towards acetylthiocholine than butyrylthiocholine. The specific activity (units/mg) of the synthetic peptide was about 123700 times less than that of the purified AChE. 相似文献
868.
Moses Julia P. Inayathullah N. Mohammed Murugesan Muthu Andrews Maneesha E. Balasubramanian M. P. Jayakumar Rajadas 《International journal of peptide research and therapeutics》2003,10(1):25-32
Summary Conductometry, circular dichroism and fluorescence spectroscopy are the techniques employed to investigate the effect of added
calcium ions and other monovalent and divalent metal ions on aqueous solutions of nonionic peptide aggregates, Boc-Leu-Asn-OEt
(1). It is observed that among all the metal ions studied, Ca2+ ions facilitate the aggregation of the peptide. The interior dielectric constant of the micelles (ε) was found to depend
upon the proportion of Ca2+ complexed peptide with the peptide mononers in the micelles. When Ca2+ ion becomes 1/4th of the peptide concentration, there is a structural transition leading to drastic change in the interior
of the micro dielectric constant (ɛ
m). 相似文献
869.
Periasamy Balasubramanian R Jayakumar Prashant Shambharkar N Unnamalai S Karutha Pandian N Selvamuthu Kumaraswami R Ilangovan Vaithilingam Sekar 《Applied and environmental microbiology》2002,68(1):408-411
Molecular cloning and characterization of a novel cry gene, cry32Aa, of Bacillus thuringiensis subsp. yunnanensis was carried out. The Cry32Aa protein was predicted to have a molecular mass of 139.2 kDa and was found to have an unusual 42-amino-acid-long tail at the C terminus. The cry32Aa gene was localized on the 103-MDa plasmid of the organism. Bioassays showed no toxicity against several moths and mosquitoes. However, it exhibited weak toxicity against larvae of the diamondback moth, Plutella xylostella. 相似文献
870.
Results of a study of the interaction of alkali metal salts on model aliphatic amides are reported. Lithium salts appear to interact more strongly with amides than those of other alkali metals. Spectroscopic investigations suggest that Li+ ion binds to the amide group at the carbonyl oxygen, causing a change in the spectroscopic properties and the geometry of the amide. Such binding of ions to amide groups may be of importance when one studies the spectral and conformational changes of polypeptides and proteins in high salt media. 相似文献