Lignin-solubilizing ability of actinomycetes isolated from termite (Termitidae) gut. [Streptomyces viridosporus]

Journal Article · Sun Jul 01 00:00:00 EDT 1990 · Applied and Environmental Microbiology; (USA)

OSTI ID:5961504

Pasti, M B; Crawford, D L ^[1]; Pometto, III, A L ^[2]; Nuti, M P ^[3]

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1. Univ. of Idaho, Moscow (USA)
2. Iowa State Univ., Ames (USA)
3. Univ. of Padua (Italy)

The lignocellulose-degrading abilities of 11 novel actinomycete strains isolated from termite gut were determined and compared with that of the well-characterized actinomycete, Streptomyces viridosporus T7A. Lignocellulose bioconversion was followed by (i) monitoring the degradation of ({sup 14}C)lignin- and ({sup 14}C)cellulose-labeled phloem of Abies concolor to {sup 14}CO{sub 2} and {sup 14}C-labeled water-soluble products, (ii) determining lignocellulose, lignin, and carbohydrate losses resulting from growth on a lignocellulose substrate prepared from corn stalks (Zea mays), and (iii) quantifying production of a water-soluble lignin degradation intermediate (acid-precipitable polymeric lignin). Of the assays used, total lignocellulose weight loss was most useful in determining overall bioconversion ability but not in identifying the best lignin-solubilizing strains. A screening procedure based on {sup 14}CO{sub 2} evolution from ({sup 14}C-lignin)lignocellulose combined with measurement of acid-precipitable polymeric lignin yield was the most effective in identifying lignin-solubilizing strains. For the termite gut strains, the pH of the medium showed no increase after 3 weeks of growth on lignocellulose. This is markedly different from the pattern observed with S. viridosporus T7A, which raises the medium pH considerably. Production of extracellular peroxidases by the 11 strains and S. viridosporus T7A was followed for 5 days in liquid cultures. On the basis of an increase of specific peroxidase activity in the presence of lignocellulose in the medium, the actinomycetes could be placed into the same three groups.

• OSTI ID: 5961504
• Journal Information: Applied and Environmental Microbiology; (USA), Vol. 56:7; ISSN 0099-2240
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
BACTERIA
METABOLISM
LIGNIN
BIODEGRADATION
CARBON 14 COMPOUNDS
CARBON DIOXIDE
COMPARATIVE EVALUATIONS
ENZYME ACTIVITY
STREPTOMYCES
TRACER TECHNIQUES
CARBOHYDRATES
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
DECOMPOSITION
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MICROORGANISMS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POLYSACCHARIDES
SACCHARIDES
550501* - Metabolism- Tracer Techniques