Production of LiP and MnP and Its Use of Cell-Free Culture ... - EERE by langkunxg

VIEWS: 0 PAGES: 1

									                                      Poster Presentation 1B-40

    Production of LiP and MnP and Its Use of Cell-Free Culture Broth of
   Phanerochaete chrysosporium for Biodegradation of Phenolic Compounds

              Sue Hyung Choi, Hwa Young Lee, Seung-Hyeon Moon, and Man Bock Gu*

   National Research Laboratory on Environmental Biotechnology, Gwangju Institute of Science and
            Technology ( GIST), 1 Oryong-dong, Buk-gu, Gwangju 500-712, Rep. of Korea
                         Phone: +82-62-970-2440 email: mbgu@gist.ac.kr


The effect of the dissolved oxygen (DO) concentration on the production of lignolytic enzymes and
isozyme distributions by Phanerochate chrysosporium was studied in the immobilized reactor system.
The oxygen levels significantly affected the production of lignin peroxidase (LiP) and manganese
peroxidase (MnP), as well as that of H2O2. Cell-free culture broth of Phanerochaete chrysosporium has
been adopted to biodegrade chlorophenols as model recalcitrants. Two different media compositions,
nitrogen-sufficient and limited, have been compared for distribution of isozyme and the production of
lignin peroxidase, manganese peroxidase, and other metabolites such as oxalate. The isozyme
distributions and their expression levels in both cases were significantly different based on SDS-PAGE
data and changed with increasing the culture time and DO concentrations: H1, H2, H6, and H10 (Lignin
peroxidases) appeared in nitrogen-sufficient medium but H3, H4, H5 (Manganese peroxidases) as well as
H7 and H8 (Lignin peroxidases) were found in nitrogen-limited medium. Biodegradation efficiency,
estimated by disappearance of the chemical as well as accumulation of chloride ion, of nitrogen-limited
culture broth was found to be higher than that of nitrogen-sufficient culture broth. The culture broth of
nitrogen-limited medium taken at 11 days showed the highest performance on the biodegradation of
2,4,5-chlorophenol. Usage of this cell-free culture broth may be easily applied to the biodegradation
system for highly recalcitrant chemicals because this system would not be affected by the toxicity of the
chemical as well as adsorption characteristics to the cells.

								
To top