| Autor: |
Knauf HJ; Institut für Lebensmitteltechnologie, Universität Hohenheim, Stuttgart, Germany., Vogel RF, Hammes WP |
| Jazyk: |
angličtina |
| Zdroj: |
Applied and environmental microbiology [Appl Environ Microbiol] 1992 Mar; Vol. 58 (3), pp. 832-9. |
| DOI: |
10.1128/aem.58.3.832-839.1992 |
| Abstrakt: |
Lactobacillus sake LTH677 is a strain, isolated from fermented sausage, which forms a heme-dependent catalase. This rare property is highly desirable in sausage fermentation, as it prevents rancidity and discoloration caused by hydrogen peroxide. A gene bank containing MboI fragments of chromosomal DNA from Lactobacillus sake LTH677 in Escherichia coli plasmid pBR328 was constructed. The catalase gene was cloned by heterologous complementation of the Kat- phenotype of E. coli UM2. The catalase structural gene, designated katA, was assigned to a 2.3-kb region by deletion analysis of the originally cloned fragment in plasmid pHK1000. The original chromosomal arrangement was determined by Southern hybridization. Protein analysis revealed that the catalase subunit has a molecular size of 65,000 Da and that the active catalase possesses a hexameric structure. The molecular size of the subunit deduced from the nucleotide sequence was determined to 54,504 Da. The N-terminal amino acid sequence of the 65,000-Da protein corresponded to the one deduced from the DNA sequence. After recloning of katA in the E. coli-Lactococcus shuttle vector pGKV210, the gene was successfully transferred and phenotypically expressed in Lactobacillus casei, which is naturally deficient in catalase activity. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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