Three mutations on the penicillin acylase surface (increasing the number of Lys in a defined area) were performed. They did not alter the enzyme's stability and kinetic properties; however, after immobilization on glyoxyl-agarose, the mutant enzyme showed improved stability under all tested conditions (e.g., pH 2.5 at 4 degrees C, pH 5 at 60 degrees C, pH 7 at 55 degrees C, or 60% dimethylforma...

Past analyses of sequence diversity in high-resolution protein-encoding genes have identified putative ecological species of unicellular cyanobacteria in the genus Synechococcus, which are specialized to 60°C but not 65°C in Mushroom Spring microbial mats. Because these studies were limited to only two habitats, we studied the distribution of Synechococcus sequence variants at 1°C intervals alo...

D-Xylose (D-glucose) isomerase was purified to homogeneity in yields of approx. 1 g/kg of wet cells from a strain of Arthrobacter that produces it as about 10% of total soluble protein. It is a tetramer of identical 43,114 Da subunits containing a preponderance of acidic residues and no cysteine. Partial protein sequences were determined as a step to gene cloning. It requires Mg2+, Co2+ or Mn2+...

The inactivation kinetics of an α-amylase enzymatic time-temperature integrator (TTI) from Bacillus subtilis (BAA) under continuous-flow microwave (MW) and conventional heating conditions were evaluated compared in this study. TTI dispersed a buffer solution (pH 5.0 to 6.9) at 20 °C initially, it was continuously circulated through two helical coils connected series for heating. positioned dome...

The structural stability of white spot syndrome virus (WSSV) capsids at high salinity, high temperature and various pH values was studied. To obtain the viral capsids, the nucleocapsids were treated with high salinity. The results showed that high salinity treatment can cause the dissociation of VP15 and most of VP95 from the nucleocapsid, but there were no noticeable alterations in morphology ...

The analytical characterization of biopharmaceuticals is a fundamental step in the early stages of development and prediction of their behavior in bioprocesses. Protein aggregation in particular is a common issue as it affects all stages of product development. In the present work, we investigate the stability and the aggregation kinetics of A33Fab, a therapeutically relevant humanized antibody...

the formation constants (log k), of the complexes formed between a number of amino acids(glycine , l-valine and l-alanine) with p-sulfonatocalix [4] arene at varying temperatures (25± 0.1to 65 ± 0.1 °c) in aqueous solutions and at natural ph of p-sulphonato-calix [4] arene (ph=3.2) bymeans of uv-vis spectrophotometeric technique have been investigated. at this ph the guestmolecule is in its cat...

the hydrolysis of cadmium nitrate was studied spectrophotometrically at different ionic strengthsof sodium perchlorate in a wide ph range, 1-12, and at 25 c. least squares calculations areconsistent with the formation of m(oh)+, m(oh)2, m(oh)3- and m(oh)42- species, which m iscd2+. the dependency on ionic strength in the background electrolyte solutions was taken intoaccount by using a debye-hu...