Cytokinetic and structural responses of the rat small intestine to riboflavin depletion

The penicillin acylase gene (pac) amplified by polymerase chain reaction (PCR) from Escherichia coli (E.coli) ATCC11105 genomic DNA was cloned into pUC9, pEMBL9+ and pCP40 vectors. A penicillin acylase precursor was overexpressed at 26 degrees C from pac-pEMBL9+ and pac-pCP40 constructs transformed into E.coli strains JM109 and pCI857 containing HB101, respectively. With the thermo-inducible pac-pCP40 construct some level of mature alpha and beta subunits and varying degrees of enzyme activity were also detected.