Clostridium sp. SAIV produces a high level of extracellular xylanase when grown on either xylan or xylose (520 and 480 mU ml-1). β-Xylosidase enzyme is cell-bound. Clostridium sp.SAIV showed growth on filter paper cellulose, but growth decreased with repeated transfer on this substrate. However, cellulase enzymes were expressed and continued degradation of cellulose occurred when the organism was grown on xylose plus cellulose. © 1991.

T S Chandra

Department Of Biotechnology

M.V.S.Murty

Bacteria

FUELS - MATERIALS

GASOLINE - ADDITIVES

CELLULASE ENZYMES

CLOSTRIDIUM SP.

Xylanase

xylose

Enzymes

CELLULASE

Xylan

XYLAN ENDO 1,3 BETA XYLOSIDASE

ANAEROBIC METABOLISM

article

CLOSTRIDIUM

enzyme activity

nonhuman

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Expression of xylanase and cellulase enzymes in a newly isolated Clostridium sp.SAIV

Enzyme and Microbial Technology

A Clostridium strain PXYL1 was isolated from a cold-adapted cattle manure biogas digester at 15°C. It could grow at temperatures as low as 5°C up to 50°C with highest specific growth rate at 20°C and is a psychrotroph. It produced extracellular hydrolytic enzymes namely xylanase, endoglucanase, β-xylosidase, β-glucosidase and filter paper cellulase, all of which had maximal activity at 20°C. The induction of xylanase was highest on birch wood xylan (37 IU{mg protein}-1) compared with xylose (1.11 IU{mg protein}-1), cellobiose (1.43 IU{mg protein}-1) and glucose (no activity). The xylanase was thermolabile with a half-life of 30 min at 40°C and 8 min at 50°C but stable for over 2 h at 20°C. The crude enzyme released reducing sugars (1.25 g l-1) from finger millet flour at 20°C, while commercial food-grade xylanases showed no hydrolysis at this temperature. This is the first report of a Clostridium strain growing at 20°C and producing an array of xylanolytic and cellulolytic enzymes, possessing low temperature optima of 20°C, which may facilitate degradation of plant fibre under low-temperature conditions. © 2003 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.

Fulltext

FEMS Microbiology Letters

A novel cold-tolerant Clostridium strain PXYL1 isolated from a psychrophilic cattle manure digester that secretes thermolabile xylanase and cellulase

The fermentability of commercial xylans and municipal waste hemicelluloses in the presence of Clostridium sp. (C.SAIV; ATCC 700188) has been evaluated. Teak, deal wood, banana stalk and bagasse of the municipal waste contained significant amounts (approx. 12%-23%) of hemicellulose. Under optimized growth conditions, the growth rate of C.SAIV was improved as indicated by an increase in the concentration of ethanol in the culture broth. Commercial xylans were utilized fairly efficiently and ethanol formed from larch wood xylan and bagasse hemicellulose was at least 64 mM. The amount of ethanol formed from the bagasse hemicellulose was at least three times higher than any other reported value. The current study also indicated that the source and composition of hemicellulose played an important role in determining the fermentability of the substrate for some microorganisms.

Applied Microbiology and Biotechnology

Fermentability of hemicelluloses extracted from municipal waste and commercial xylans by Clostridium sp.

By enrichment with xylose, nine mesophilic strains of anaerobic bacteria were obtained from various sources. Two isolates appear to belong to the genus Eubacterium. Six other strains belong to the genus Clostridium. Three of the isolated strains utilized larch wood xylan. The percentage of utilization of xylose and xylan and the yield of fermentation end products - viz. acetic acid and butyric acid-are equivalent to that of Clostridium acetobutylicum (ATCC 824) and reported thermophilic strains. © 1989 Kluwer Academic Publishers.

Antonie van Leeuwenhoek

Isolation and characterization of xylose- and xylan-utilizing anaerobic bacteria

ScienceAsia

10.2306/scienceasia1513-1874.1989.15.109

Applied and Environmental Microbiology

Fermentation of xylans by Butyrivibrio fibrisolvens and other ruminal bacteria.

Fermentation of d-Xylose to Ethanol by Genetically Modified Klebsiella planticola

Biotechnology Letters

Induction and glucose repression of xylanase from a color variant strain ofAureobasidum pullulans

Journal	Data powered by TypesetEnzyme and Microbial Technology
Publisher	Data powered by TypesetElsevier Inc
ISSN	01410229
Open Access	No