Inactivation of the regulatory gene SHJG0322 . (A) Schematic replacement of an internal 610 bp fragment of SHJG0322 with aac(3)IV-oriT cassette. (B) PCR analysis of strain 5008 and SHJG0322 mutant JG27. (C) VAL-A production in strain 5008, mutant JG27, JG27/pJTU5287 (with PermE* promoter), and JG27/pJTU5288 (with native promoter) cultivated at 30°C or 37°C. Mean values of three independent experiments with SD are indicated by error bars. (D) Relative transcriptional levels of valA and valK in strain 5008 or JG27 at 37°C against 30°C.