skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Selection and characterization of mutants of Phanerochaete chrysosporium exhibiting ligninolytic activity under nutrient-rich conditions

Abstract

Synthesis of the ligninolytic system of the wood-degrading fungus Phanerochaete chrysosporium is induced during secondary metabolism, brought about by nitrogen, carbon, or sulfur starvation. We describe here a strategy for selection of mutants which are ligninolytic (lignin{yields}CO{sub 2}) and overproduce lignin-degrading enzymes (ligninases) under nutrient-rich conditions (during primary metabolism). The strategy is based on using an adduct of lysine and a lignin model compound. Ligninase-dependent oxidation of this adduct releases free lysine, which complements the lysine requirements of a lysine auxotroph. Accordingly, a lysine auxotroph was mutagenized by UV irradiation and survivors were plated onto medium containing the adduct and high ammonia nitrogen. Four mutants which overproduce the ligninase isozymes were isolated by this procedure. Further characterization of one of the mutants, PSBL-1, indicated that the predominant isozymes produced are H1 (pI = 4.7) and H2 (pI = 4.4). The ligninase activity of PSBL-1, measured by veratryl alcohol oxidation, peaks on day 5 at over 1,000 U{center dot}liter{sup {minus}1}. The mutant PSBL-1 was also able to degrade ({sup 14}C)lignin to {sup 14}CO{sub 2}, indicating that the complete ligninolytic system is deregulated.

Authors:
;  [1]
  1. Pennsylvania State Univ., University Park (USA)
Publication Date:
OSTI Identifier:
5985606
Resource Type:
Journal Article
Journal Name:
Applied and Environmental Microbiology; (USA)
Additional Journal Information:
Journal Volume: 56:8; Journal ID: ISSN 0099-2240
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; 54 ENVIRONMENTAL SCIENCES; 59 BASIC BIOLOGICAL SCIENCES; LIGNIN; BIODEGRADATION; PHANEROCHAETE; BIOLOGICAL PATHWAYS; CARBON 14 COMPOUNDS; CARBON DIOXIDE; ENZYME ACTIVITY; ISOENZYMES; LYSINE; MUTAGENESIS; MUTANTS; PEROXIDASES; TRACER TECHNIQUES; ULTRAVIOLET RADIATION; AMINO ACIDS; CARBOHYDRATES; CARBON COMPOUNDS; CARBON OXIDES; CARBOXYLIC ACIDS; CHALCOGENIDES; CHEMICAL REACTIONS; DECOMPOSITION; ELECTROMAGNETIC RADIATION; ENZYMES; EUMYCOTA; FUNGI; ISOTOPE APPLICATIONS; LABELLED COMPOUNDS; ORGANIC ACIDS; ORGANIC COMPOUNDS; OXIDES; OXIDOREDUCTASES; OXYGEN COMPOUNDS; PLANTS; POLYSACCHARIDES; RADIATIONS; SACCHARIDES; 090900* - Biomass Fuels- Processing- (1990-); 540211 - Environment, Terrestrial- Basic Studies- Radiometric Techniques- (1990-); 550501 - Metabolism- Tracer Techniques

Citation Formats

Tien, Ming, and Myer, S B. Selection and characterization of mutants of Phanerochaete chrysosporium exhibiting ligninolytic activity under nutrient-rich conditions. United States: N. p., 1990. Web.
Tien, Ming, & Myer, S B. Selection and characterization of mutants of Phanerochaete chrysosporium exhibiting ligninolytic activity under nutrient-rich conditions. United States.
Tien, Ming, and Myer, S B. Wed . "Selection and characterization of mutants of Phanerochaete chrysosporium exhibiting ligninolytic activity under nutrient-rich conditions". United States.
@article{osti_5985606,
title = {Selection and characterization of mutants of Phanerochaete chrysosporium exhibiting ligninolytic activity under nutrient-rich conditions},
author = {Tien, Ming and Myer, S B},
abstractNote = {Synthesis of the ligninolytic system of the wood-degrading fungus Phanerochaete chrysosporium is induced during secondary metabolism, brought about by nitrogen, carbon, or sulfur starvation. We describe here a strategy for selection of mutants which are ligninolytic (lignin{yields}CO{sub 2}) and overproduce lignin-degrading enzymes (ligninases) under nutrient-rich conditions (during primary metabolism). The strategy is based on using an adduct of lysine and a lignin model compound. Ligninase-dependent oxidation of this adduct releases free lysine, which complements the lysine requirements of a lysine auxotroph. Accordingly, a lysine auxotroph was mutagenized by UV irradiation and survivors were plated onto medium containing the adduct and high ammonia nitrogen. Four mutants which overproduce the ligninase isozymes were isolated by this procedure. Further characterization of one of the mutants, PSBL-1, indicated that the predominant isozymes produced are H1 (pI = 4.7) and H2 (pI = 4.4). The ligninase activity of PSBL-1, measured by veratryl alcohol oxidation, peaks on day 5 at over 1,000 U{center dot}liter{sup {minus}1}. The mutant PSBL-1 was also able to degrade ({sup 14}C)lignin to {sup 14}CO{sub 2}, indicating that the complete ligninolytic system is deregulated.},
doi = {},
url = {https://www.osti.gov/biblio/5985606}, journal = {Applied and Environmental Microbiology; (USA)},
issn = {0099-2240},
number = ,
volume = 56:8,
place = {United States},
year = {1990},
month = {8}
}