Increased cellulose production from sucrose with reduced levan accumulation by an Acetobacter strain harboring a recombinant plasmid.
Cellulose production from sucrose by Acetobacter strains is accompanied by the accumulation of a water-soluble polysaccharide, called levan. To improve cellulose productivity, a levansucrase-deficient mutant, LD-2, was derived from Acetobacter strain 757 and used as a host for the construction of recombinant strains. An LD-2 mutant harboring a plasmid containing the sucrase gene, sucZE3, from Zymomonas mobilis together with zliS, a gene that encodes a secretion-activating factor under the control of the Escherichia coli lac promoter, had sucrase activity and produced much cellulose and little levan in a medium containing sucrose. In addition, a mutant levansucrase gene, mutant sacB, from Bacillus subtilis, which encodes a protein with little levan-forming activity, was generated by site-directed mutagenesis and introduced into the LD-2 mutant. This introduction also resulted in the higher cellulose productivity and little levan.
Tonouchi
N
N
Bio-Polymer Research Co., Ltd., Kanagawa, Japan.
Yanase
H
H
Kojima
Y
Y
Tsuchida
T
T
Yoshinaga
F
F
Horinouchi
S
S
D000091:Acetobacter / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*; D002482:Cellulose / Q000096:biosynthesis*; D017931:DNA Primers; D004274:DNA, Recombinant / Q000235:genetics*; D005630:Fructans / Q000378:metabolism*; D010957:Plasmids / Q000235:genetics*; D013395:Sucrose / Q000378:metabolism*
D017931:DNA Primers; D004274:DNA, Recombinant; D005630:Fructans; D013395:Sucrose; D002482:Cellulose