Protein and Peptide Letters - Volume 8, Issue 1, 2001

In a rapid purification procedure, two distinct type II topoisomerase activities (decatenation and catenation) have been isolated from the whole cell extracts of Trypanosoma brucei brucei. Both decatenating and catenating activities were detected in the cell extracts, but these two activities were separated in the last step of purification. These two activities were found to be independent of each other and competent both in the pr Read More

From the crude snake venom of Bothrops moojeni, a homodimeric lectin was purified by affinity chromatography in lactose and was named BMooL. This lectin appeared to be a glycoprotein because it reacted with Schiffs reagent. The hemagglutinating activity of BMooL is inhibited by galactoside, EDTA, EGTA and DTT. The amino acid analysis of BMooL showed a high content of acidic residues and its N-terminal sequen Read More

Eight peptides were isolated from Bothrops moojeni venom by filtration followed by HPLC. MALDI mass spectroscopy and Edman degradation determined the purity, Mr and sequence of the peptides, respectively. Three (BmP7, BmP8 and BmvP11) of them were homologues with the biologically active B. jararaca bradykinin potentiating peptides while the other with peptides or protein from different sources.

POU box gene qBrn -2 exhibits restricted expression pattern in quail neurogenesis and myogenesis. Here we report isolation of a N-terminal segment (P207) of qBrn-2 expressed in E. coli and tips on preparation of a recombinant protein. Recombinant P207 was purified and migrated as a single band on SDS-PAGE with the same apparent molecular mass as predicted. In the expression of P207 by pET 3b vector, IPTG conce Read More

The stability of BTCI has been investigated as function of pH and temperature, following its inhibitory activity against trypsin. The isolated inhibitor of 9,084 Da is stable over pH 3 to 10 at 25 o C. BTCI showed high thermal stability ranging from 25 to 95 o C at pH 3.0 and 7.0. However, the protein lost about 20 percent of its inhibitory activity over 75 o C at pH 8.2. The results indicated that BTCI is extremely stable to heat an Read More

Present work encompasses a detailed solution and solid phase NMR spectroscopic studies on oxybenzotriazole based coupling reagents namely HBTU (1), NBTU (2) and BOP (3). The present finding unequivocally establish that the correct structure of oxybenzotriazole based coupling reagents both in the solution and solid states are benzotriazolyl N-oxides as shown in 1a, 2a and 3a and not the uronium form as represented in t Read More

Amides of Z- and Boc protected amino acids have been prepared by using p-toluenesulphonyl chloride (TsCI) for the activation of carboxyl group. The resulting mixed carboxylic-sulphonic anhydride intermediate was treated in situ with an excess of 25 percent ammonia solution. All the amino acid amides prepared were obtained as crystalline solids in good yield and purity.

CD spectral studies of VPDLLADLK, a synthetic peptide shows that it undergoes a conformational transition from an unordered structure to a more ordered structure from a polar to a non-polar homogeneous medium. In microheterogeneous media like SDS, CTAB micelles and DMPC lipid bilayer, the peptide exhibits a more stable alpha- helical structure. The helical conformation is stabilized in DMPC lipid bilayer. Homology Read More

L(+)-2,3 -Butanediol dehydrogenase (L-BDH) from Brevibacterium saccharolyticum C-1012 has been crystallized by the hanging drop vapor diffusion method with polyethylene glycol 4000 as the precipitant. Crystals of L-BDH belong to the triclinic system, space group P1 with cell dimensions a = 60.8 A, b = 69.2 A, c = 127.4 A , alpha = 96.1 , beta = 100.2 and gama=109.6 . Crystals diffracted to 2.0 A resolution on Read More

Crystals of human carbonic anhydrase II with a specific point mutation, His 64 to Ala, have been grown in a solution of ammonium sulfate in the presence of mercury chloride. The crystals appear in approximately two weeks and belong to the monoclinic space group P21, with unit cell parameters of a = 42.2 A, b = 41.4 A, c = 71.9 A , beta= 104.2 o and one carbonic anhydrase molecule in the asymmetric unit. The cry Read More

Escherichia coli riboflavin synthase crystallizes at 22 C in the presence of 7-10percent by volume diglyme, 20-50 mM MgCl2 and pH 7.0. In this medium diffraction quality crystals are routinely obtained within 5 h and they are stable for 10 weeks. The crystals are orthogonal in space group P212121 with unit cell dimensions of a=52.4 A , b = 62.1 A, c = 218.8 A. A 97percent complete data set was collected at 2.1 A resolution.