Enzymology of lignocellulose bioconversion by Streptomyces viridosporus

Miscellaneous · Sun Jan 01 00:00:00 EST 1989

OSTI ID:6896660

Ramachandra, M

Significant progress has been made in lignin biodegradation research since 1983, when lignin peroxidases were discovered in fungi. A similar breakthrough in bacterial lignin biodegradation research is anticipated. Several laboratories have successfully demonstrated the ability of bacteria to mineralize ({sup 14}C)-lignin lignocelluloses as well as {sup 14}C-labelled synthetic lignins. Attempts are being made to identify the key enzymes involved. In this dissertation, two studies are presented which address the enzymology of lignin biodegradation by Streptomyces viridosporus. The first study compares selected extracellular enzyme of wild-type and genetically manipulated strains with enhanced abilities to produced a water soluble lignin degradation intermediate, designated acid-precipitable polymeric lignin (APPL). UV irradiation mutant T7A-81 and protoplast fusion recombinant SR-10 had higher and longer persisting peroxidase, esterase, and endoglucanase activity than did the wild type strain T7A. An extracellular lignocellulose-induced peroxidase with some similarities to fungal ligninases was described for the first time in Streptomyces. The second study describes purification and characterization of an extracellular lignin peroxidase produced by S. viridosporus T7A. This is the first report of a lignin peroxidase in any bacterium.

• Research Organization: Idaho Univ., Moscow, ID (USA)
• OSTI ID: 6896660
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
CELLULASE
ENZYME ACTIVITY
ESTERASES
LIGNIN
BIODEGRADATION
PEROXIDASES
CHEMICAL COMPOSITION
CARBON 14 COMPOUNDS
FRACTIONATION
RADIATION INDUCED MUTANTS
STREPTOMYCES
TRACER TECHNIQUES
ULTRAVIOLET RADIATION
BACTERIA
CARBOHYDRATES
CHEMICAL REACTIONS
DECOMPOSITION
ELECTROMAGNETIC RADIATION
ENZYMES
GLYCOSYL HYDROLASES
HYDROLASES
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MICROORGANISMS
MUTANTS
O-GLYCOSYL HYDROLASES
ORGANIC COMPOUNDS
OXIDOREDUCTASES
POLYSACCHARIDES
RADIATIONS
SACCHARIDES
SEPARATION PROCESSES
550501* - Metabolism- Tracer Techniques
560130 - Radiation Effects on Microorganisms