Cloning and Expression of the Benzoate Dioxygenase Genes from Rhodococcus sp. Strain 19070
| Autor: | D. Matthew Eby, S. Haddad, Ellen L. Neidle |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2001 |
| Předmět: |
Molecular Sequence Data
Genetics and Molecular Biology Biology Reductase medicine.disease_cause Applied Microbiology and Biotechnology Benzoates Homology (biology) Plasmid Dioxygenase medicine Escherichia coli Rhodococcus Phylogeny Ecology Sequence Homology Amino Acid Nucleic acid sequence biology.organism_classification Molecular biology Recombinant Proteins Open reading frame Biodegradation Environmental Biochemistry Genes Bacterial Multigene Family Oxygenases Food Science Biotechnology |
| Popis: | The bopXYZ genes from the gram-positive bacterium Rhodococcus sp. strain 19070 encode a broad-substrate-specific benzoate dioxygenase. Expression of the BopXY terminal oxygenase enabled Escherichia coli to convert benzoate or anthranilate (2-aminobenzoate) to a nonaromatic cis -diol or catechol, respectively. This expression system also rapidly transformed m -toluate (3-methylbenzoate) to an unidentified product. In contrast, 2-chlorobenzoate was not a good substrate. The BopXYZ dioxygenase was homologous to the chromosomally encoded benzoate dioxygenase (BenABC) and the plasmid-encoded toluate dioxygenase (XylXYZ) of gram-negative acinetobacters and pseudomonads. Pulsed-field gel electrophoresis failed to identify any plasmid in Rhodococcus sp. strain 19070. Catechol 1,2- and 2,3-dioxygenase activity indicated that strain 19070 possesses both meta - and ortho -cleavage degradative pathways, which are associated in pseudomonads with the xyl and ben genes, respectively. Open reading frames downstream of bopXYZ , designated bopL and bopK , resembled genes encoding cis -diol dehydrogenases and benzoate transporters, respectively. The bop genes were in the same order as the chromosomal ben genes of P. putida PRS2000. The deduced sequences of BopXY were 50 to 60% identical to the corresponding proteins of benzoate and toluate dioxygenases. The reductase components of these latter dioxygenases, BenC and XylZ, are 201 residues shorter than the deduced BopZ sequence. As predicted from the sequence, expression of BopZ in E. coli yielded an approximately 60-kDa protein whose presence corresponded to increased cytochrome c reductase activity. While the N-terminal region of BopZ was approximately 50% identical in sequence to the entire BenC or XylZ reductases, the C terminus was unlike other known protein sequences. |
| Databáze: | OpenAIRE |
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