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The effects of culture media on the production of xyIan-degrading enzymes by Streptomyces chattanoogensis UAH 23

✍ Scribed by C. L. López Fernández; J. Rodríguez; J. Soliveri; J. L. Copa-Patiño; M. I. Pérez-Leblic; M. E. Arias


Publisher
John Wiley and Sons
Year
1995
Tongue
English
Weight
484 KB
Volume
35
Category
Article
ISSN
0233-111X

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✦ Synopsis


The production of 4 extracellular xylanolytic enzymes, arabinofuranosidase, endoxylanase, ,5-xylosidase ' and acetyl esterase during the growth of Streptomyces chattanoogensis UAH 23 in basal salts media containing different carbon sources was examined. The highest enzyme activities were generally detected when arabinoxylan was used as the carbon source, with the exception of acetyl-esterase where greatest activity was detected when ball-milled straw was used as carbon source. A comparison of enzyme activities revealed that the specific activity of endoxylanase (3.15 U/mg protein) was greater than those of the other three enzyme activities (44.11,5.77 and 2.04 mU/mg protein for acetyl-esterase, a-L-arabinofuranosidase and /3-xylosidase, respectively). Cellulase activity could not be detected throughout the study.

Characterization of the endoxylanase activity revealed that two optima pH could be detected (7.0 and 8.0) and was stable at alkaline pH values between 6.5 and 8.5. The optimum temperature was 55 "C with the enzyme stable for one hour at 60 "C. Activity staining of non denaturedpolyacrylamide gels containing culture supernatants revealed the presence of two active endoxylanase bands. The result suggest that two endoxylanase enzymes with different pH optimas are secreted by Streptomyces chattanoogensis UAH 23.