DE WAAL, Paulus Petrus,HANEMAAIJER, Laurens Leendert
申请号：
EPEP2019/085483
公开号：
WO2020/127144A1
申请日:
2019.12.17
申请国别(地区):
EP
年份:
2020
代理人:
摘要：
The present invention relates to a method for obtaining a bacteriophage insensitive mutant (BIM) of a lactic acid bacterium parent strain suitable for food and feed fermentation. Further, the present invention relates to a method for the construction of a bacteriophage insensitive lactic acid bacterium whereby the phage resistance is conferred by a mechanism other than CRISPR. A preferred lactic acid bacterium is Streptococcus thermophilus. The invention provides a method for obtaining a non-CRISPR bacteriophage-insensitive mutant (BIM) from a lactic acid bacterium parent strain comprising exposing said parent strain to at least one virulent bacteriophage which expresses a gene encoding an anti- CRISPR protein, growing surviving lactic acid bacteria for at least one cycle in milk in the presence of said at least one bacteriophage which expresses a gene encoding an anti-CRISPR protein, isolating BIMs resulting therefrom, characterizing and selecting a BIM which when compared to the parent strain is insensitive to more bacteriophages, has an improved stability of the acquired bacteriophage resistance, and has an acidification profile in milk which is at least comparable to or improved when compared to said parent strain.La présente invention concerne un procédé d'obtention d'un mutant insensible aux bactériophages (BIM) d'une souche parente de bactérie lactique appropriée pour la fermentation d'aliments et de fourrage. En outre, la présente invention concerne un procédé de construction d'une bactérie lactique insensible aux bactériophages, la résistance aux phages étant conférée par un mécanisme autre que CRISPR. Une bactérie d'acide lactique préférée est Streptococcus thermophilus. L'invention concerne un procédé d'obtention d'un mutant insensible aux bactériophages non CRISPR (BIM) à partir d'une souche parente de bactérie lactique comprenant l'exposition de ladite souche parente à au moins un bactériophage virulent exprimant un gène codant pour une protéine anti-CR
