FIG 5.

ABM production of the constructed strains. pCK series are strains containing replicating plasmids. SCAKs are strains with chromosomally integrated mutations. The genes cloned in each construct for overexperssion are as follows: for pCK4, sahH; for pCK5, metK-sahH; for pCK6, metE; for pCK7, metK-sahH-metE; for SCAK4, ask-asd; and for SCAK5, metY-X-SO-ask-asd. Each production level is the average of at least three experimental replicates; the standard error is represented by an error bar. **, P < 0.01; *, P < 0.05.