Conjugal transfer of lactose-fermenting ability fromStreptococcus lactis C2 toLeuconostoc cremoris CAF7 yieldsLeuconostoc that ferment lactose and produce diacetyl |
| |
Authors: | Huai-Jen Tsai Dr W E Sandine |
| |
Institution: | (1) Department of Microbiology, Oregon State University, 97331-3804 Corvallis, OR, U.S.A.;(2) Present address: Development Center for Biotechnology, Taipei, Taiwan, R.O.C. |
| |
Abstract: | Summary Conjugation between lactose-fermenting (Lac+)Streptococcus lactis C2 and Lac–
Leuconostoc cremoris CAF7 was performed. The frequency of Lac+ transfer was 1.5 · 10–2 per donor cell. Lac+
Leuconostoc transconjugants could ferment lactose significantly faster than wild-type cells. When grown in litmus milk fortified with 0.2% yeast extract, Lac+ transconjugants reached pH 4.68 within 24 h at 30°C and produced diacetyl. The identity of the transconjugants asLeuconostoc derivatives was confirmed by their resistance to phage c2 and to vancomycin (>500 g/ml), and by growth on selective medium containing azide. Plasmid profiles of 10 transconjugants showed two unique patterns. A novel enlarged plasmid was found. Southern blot hybridization revealed some homology with the 30 Md Lac+ plasmid of donor, recipient and the transconjugants, as well as with some of the remaining plasmids of the donor.Technical Paper No. 7953, Oregon Agricultural Experiment Station. |
| |
Keywords: | Conjugation Transconjugant Plasmid Southern-blot hybridization Diacetyl |
本文献已被 SpringerLink 等数据库收录! |
|