We isolated a thermophile, Bacillus sp. YM-1 which abundantly produced the thermostable D-amino acid aminotransferase (EC 2.6.1.21; D-AAT), and cloned the enzyme gene into E. coli. The primary structure of D-AAT was found to be homologous with that of branched-chain L-amino acid aminotransferase (EC 2.6.1.42; BCAT) of E. coli. Both enzymes are unique in their stereospecificity of proR C-4' hydr...

BACKGROUND Mannans are key components of lignocellulose present in the hemicellulosic fraction of plant primary cell walls. Mannan endo-1,4-beta-mannosidases (1,4-beta-D-mannanases) catalyze the random hydrolysis of beta-1,4-mannosidic linkages in the main chain of beta-mannans. Biodegradation of beta-mannans by the action of thermostable mannan endo-1,4-beta-mannosidase offers significant tech...

Lipases are diversified enzymes in their properties and substrate specificity, which make them attractive tools for various industrial applications. In this study, an alkaline thermostable lipase producing bacteria were isolated from soil of different regions of Isfahan province (Iran) and its lipase was purified by ammonium sulfate precipitation and ion exchange chromatography. To select a the...

The hydrodynamic parameters of the thermostable formyltetrahydrofolate synthetase from Clostridium thermoaceticum have been measured in the ultracentrifuge at 20”. &J,~ = 9.86 f 0.20 S;vzo = 0.752 f 0.011 cc per g; and molecular weight = 244,000 f 9,000. Calculations based on these parameters give a frictional ratio, f/f0 = 1.27 f 0.11, and a Stokes radius of 53.0 f 4.8 A. The sedimentation con...

A thermostable amylopullulanase producing Clostridium thermosulfurogenes SVM17 was selected for the study. Culture conditions for growth and enzyme production parameters were optimized. Enzyme synthesis occurred at temperatures between 50 and 70°C with an optimum of 60°C. The enzyme production was observed between pH 4.0 and 9.0 with an optimum of pH 7.5. Maximum growth and enzyme production wa...

A thermostable enzyme capable of digesting d-ribose (yeast) nucleic acid was first described by W. Jones in 1920 (1). A partial purification of this enzyme with acetone was carried out by Dubos and Thompson who called the enzyme ribonuclease (2). Kunitz described the preparation and properties of a crystalline protein he isolated from beef pancreas which appeared to be the same as the ribonucle...

The kinetics of thermal inactivation of copper-containing amine oxidase from lentil seedlings were studied in a 100 mM potassium phosphate buffer, pH 7, using putrescine as the substrate. The temperature range was between 47-60 degrees C. The thermal inactivation curves were not linear at 52 and 57 degrees C; three linear phases were shown. The first phase gave some information about the number...

Alkalophilic Bacillus sp. strain NG-27 produces a 42-kDa endoxylanase active at 70 degrees C and at a pH of 8.4. The gene for this endoxylanase was cloned and sequenced. The gene contained one open reading frame of 1,215 bases. An active site characteristic of the family 10 beta-glycanases was recognized between amino acids 303 and 313, with the active glutamate at position 310. Though highly t...

actinomycetes are an uncommon agent of human infections and its pathogenic factors are not known. the present study reports a rare case isolation of an actinomycete from a woman pleural fluid; the strain was identified by 16s rrna gene sequence analysis. this strain was tested to produce an extracellular protease that hydrolysis gelatin, casein and hemoglobin on agar mediums. the purification o...

sn-Glycerol-1-phosphate dehydrogenase is responsible for the formation of sn-glycerol-1-phosphate, the backbone of membrane phospholipids of Archaea. This activity had never been detected in cell-free extract of Sulfolobus sp. Here we report the detection of this activity on the thermostable ST0344 protein of Sulfolobus tokodaii expressed in Escherichia coli, which was predicted from genomic in...