Purification and characterization of MerR, the regulator of the broad-spectrum mercury resistance genes in Streptomyces lividans 1326

1999 ◽  
Vol 262 (1) ◽  
pp. 154-162 ◽  
Author(s):  
D. Rother ◽  
R. Mattes ◽  
J. Altenbuchner
Keyword(s):  
Resistance Genes ◽  
Broad Spectrum ◽  
Streptomyces Lividans ◽  
Mercury Resistance ◽  
Purification And Characterization

Purification and characterization of a β-glucosidase from Streptomyces lividans 66

1990 ◽  
Vol 36 (1) ◽  
pp. 53-56 ◽  
Author(s):  
Anca Mihoc ◽  
Dieter Kluepfel
Keyword(s):  
High Performance Liquid Chromatography ◽  
Molecular Sieve ◽  
Type Strain ◽  
High Performance ◽  
Wild Type Strain ◽  
Streptomyces Lividans ◽  
Wild Type ◽  
Purification And Characterization ◽  
Anion Exchange Column

An intracellular β-1, 4-D-glucosidase (EC 3.2.1.21) was isolated from the mutant strain HP-3 of Streptomyces lividans 66 which produced about 12 times more enzyme than the wild-type strain. The purification was carried out by anion exchange column chromatography followed by high-performance liquid chromatography on DEAE and on molecular sieve columns. The enzyme is glycosylated and has an apparent Mr of 51 000 and a pI of 4.3. Its activity was optimal at pH 6.5 and at a temperature of 40 °C. The Km and the Vmax on cellobiose were 3.1 mM and 65.6 μmol min−1 mg−1 of enzyme. Key words: β-glucosidase, Streptomyces lividans, purification, characterization.

scholarly journals Purification and characterization of a new xylanase (xylanase B) produced by Streptomyces lividans 66

1990 ◽  
Vol 267 (1) ◽  
pp. 45-50 ◽  
Author(s):  
D Kluepfel ◽  
S Vats-Mehta ◽  
F Aumont ◽  
F Shareck ◽  
R Morosoli
Keyword(s):  
Streptomyces Lividans ◽  
Genetically Engineered ◽  
Cross Reaction ◽  
Short Chain ◽  
Purification And Characterization ◽  
Specific Antibodies ◽  
Hydrolysis Products

A new extracellular xylanase produced by Streptomyces lividans 66 was isolated from a genetically engineered clone of that strain. This enzyme, named xylanase B, has an Mr of 31,000 and acts specifically on xylan as an endo-type xylanase producing short-chain xylo-oligosaccharides. The activity is optimal at pH 6.5 and at a temperature of 55 degrees C, which is similar to that of the previously characterized xylanase A. Xylanase B is glycosylated and has a pI of 8.4; its Km and Vmax. values are 3.71 mg/ml and 1.96 mmol/mg of enzyme respectively. Specific antibodies raised against xylanase A show no cross-reaction with xylanase B; however, the anti-(xylanase B) antibodies react slightly with xylanase A. A comparison of the hydrolysis products obtained from oat-spelts xylan with both enzymes show that xylanase A preferentially degrades short-chain oligo-xylosides, whereas xylanase B acts on the longer, water-insoluble, molecules.

scholarly journals Purification and characterization of an α-l-arabinofuranosidase from Streptomyces lividans 66 and DNA sequence of the gene (abfA)

1994 ◽  
Vol 302 (2) ◽  
pp. 443-449 ◽  
Author(s):  
C Manin ◽  
F Shareek ◽  
R Morosoli ◽  
D Kluepfel
Keyword(s):  
Dna Sequence ◽  
Avena Sativa ◽  
Specific Activity ◽  
Gel Filtration ◽  
Streptomyces Lividans ◽  
Native Protein ◽  
Purification And Characterization ◽  
Gene Encoding ◽  
Sds Page

The gene encoding an alpha-L-arabinofuranosidase (abfA) was homologously cloned in Streptomyces lividans and its DNA sequence was determined. The enzyme was purified from the cytoplasm of the hyperproducing clone S. lividans IAF116. Its M(r) was estimated by gel filtration and found to be approx. 380,000. Since SDS/PAGE indicated a native protein of M(r) 69,000, it can be concluded that the native protein consists of several subunits of that size. The pI value was 4.6. The kinetic constants determined with p-nitrophenyl alpha-L-arabinofuranoside as substrate were a Vmax of 180 units/mg of protein and a Km of 0.6 mM. The specific activity of the purified enzyme on this substrate was 153 units/mg of protein. Optimal enzyme activity was obtained at 60 degrees C and pH 6.0. The enzyme cleaved p-nitrophenyl alpha-L-arabinofuranoside, but had no activity on a variety of other p-nitrophenyl glycosides, except on p-nitrophenyl beta-D-xylopyranoside. The enzyme showed no activity on oat-spelts (Avena sativa) xylan or arabinogalactan, but acted on beet (Beta) arabinan or arabinoxylan. Hydrolysis occurred on arabino-oligoxylosides obtained from oat-splets xylan after digestion with xylanases. Since S. lividans normally does not secrete arabinofuranosidase, this enzyme may play a role in the assimilation of arabinose moieties from arabinose-containing xylo-oligosaccharides generated by beta-xylosidases or xylanases.

Sign in / Sign up

Export Citation Format

Share Document