V. MeevootisomJ. R. SaundersMahidol UniversityUniversity of Liverpool2018-06-142018-06-141987-01-01Applied Microbiology and Biotechnology. Vol.25, No.4 (1987), 372-37814320614017575982-s2.0-0023149799https://repository.li.mahidol.ac.th/handle/20.500.14594/15325Penicillin acylase genes from Escherichia coli 194, of an overproducing mutant (194-3) of this strain, and of a similar overproducing mutant of Bacillus megaterium UN1 were cloned in E. coli DH1 on the plasmid vector pACYC184. The sizes of chromosomal DNA fragments essential for penicillin acylase production were found by Tn 1000 mutagenesis and in vitro deletions to be between 2.2 and 2.5 kb in the case of both E. coli genes and between 2.3 and 2.7 kb in the case of the mutant Bacillus gene. Restriction mapping indicated substantial sequence differences between the E. coli and B. megaterium penicillin acylase genes. Enzyme production in E. coli recombinants from both overproducing mutants was found to be constitutive and higher than in the original strains. The Bacillus penicillin acylase was produced intracellularly in E. coli recombinants, which is in contrast to the normal extracellular production of this enzyme in B. megaterium. Recombinant plasmids containing penicillin acylase genes from either source were found to be unstable in the absence of selection pressure for retention of the vector. © 1987 Springer-Verlag.Mahidol UniversityBiochemistry, Genetics and Molecular BiologyImmunology and MicrobiologyArticleSCOPUS10.1007/BF00252550