| Autor: |
Harhangi HR; Department of Microbiology, Faculty of Science, University of Nijmegen, Toernooiveld 1, NL-6525 ED, Nijmegen, The Netherlands., Akhmanova A, Steenbakkers PJ, Jetten MS, van der Drift C, Op den Camp HJ |
| Jazyk: |
angličtina |
| Zdroj: |
Gene [Gene] 2003 Sep 18; Vol. 314, pp. 73-80. |
| DOI: |
10.1016/s0378-1119(03)00705-4 |
| Abstrakt: |
Anaerobic fungi contain more than one copy of genes encoding (hemi-)cellulases in their genome. The arrangement of these genes on the chromosomes was not known. A genomic DNA (gDNA) library of Piromyces sp. E2 was screened with different probes specific for (hemi-)cellulolytic enzymes. This screening resulted in three gDNA clones with genes encoding glycoside hydrolase enzymes of families 1 (beta-glucosidase), 6 (exoglucanase) and 26 (mannanase). Each clone contained two or more genes of the same family. Comparison of the gene copies on a clone revealed that they were highly homologous, and in addition, 54-75% of the substitutions was synonymous. One of the mannanase genes contained an intron. PCR with selected primers resulted in a gDNA clone with a new representative (cel9B) of glycoside hydrolase family 9 (endoglucanase). Comparison with cel9A revealed that cel9B had 67% homology on the nucleotide level. Furthermore, three introns were present. All results of this paper taken together provided evidence for duplications of (hemi-)cellulolytic genes, which resulted in clusters of almost identical genes arranged head-to-tail on the genome. In contrast to other eukaryotes, this phenomenon appears frequently in anaerobic fungi. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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Full Text from ScienceDirect