Enhanced secretion of heterologous cyclodextrin glycosyltransferase by a mutant of Bacillus licheniformis defective in the D-alanylation of teichoic acids.
OBJECTIVE
To examine whether inactivation of the dlt operon and increased charge density of the wall enhances secretion of heterologous proteins in industrial strains of Bacillus licheniformis.


RESULTS
The dltA gene of B. licheniformis was cloned, sequenced and mutated by inserting a chloramphenicol acetyl transferase (cat) gene cassette. The mutation facilitated growth in the late exponential growth phase, increased endogenous autolysis and decreased resistance to a cationic peptide, polylysine. It was observed that dltA mutation increased the production of cyclodextrin glycosyltransferase (CGTase) by 1.5- to sevenfold depending on the growth phase, but decreased the production of penicillinase by twofold.


CONCLUSIONS
The results suggest that the d-alanylation of teichoic acids is an element that can be used to improve the production of some secretory proteins in industrial applications based on this important industrial microorganism.
Craynest
M
M
Vaccine Development Laboratory, National Public Health Institute, Helsinki, Finland.
Jørgensen
S
S
Sarvas
M
M
Kontinen
V P
VP
D000409:Alanine / Q000378:metabolism*; D001407:Bacillus / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D003001:Cloning, Molecular; D005964:Glucosyltransferases / Q000378:metabolism*; D007218:Industrial Microbiology; D009154:Mutation; D013682:Teichoic Acids / Q000378:metabolism*
D013682:Teichoic Acids; D005964:Glucosyltransferases; C019963:cyclomaltodextrin glucanotransferase; D000409:Alanine