An improved method for screening alpha-acetolactate producing mutants

alpha-Acetolactate-deficient Lactococcus lactis ssp. lactis biovar. diacely lactis are utilised in several industrial processes for producing diacetyl and alpha-acetolactate. They can be selected by screening after random muta genesis. We improved a previously described screening method [Monnet, C., S chmitt, P., Divibs, C., 1997. Appl. Environ. Microbiol. 63, 793-795], which makes it possible to screen up to 1000 colonies per agar plate, whereas th e previous method allowed to screen only 60 colonies per agar plate. The ne w screening method facilitates selection of alpha-acetolactate-deficient mu tants. (C) 1999 Elsevier Science B.V. All rights reserved.