Purification, characterization, and gene cloning of glucose-1-phosphatase from Citrobacter braakii.
Citrobacter braakii produced an intracellular acid glucose phosphatase (AgpC) which was purified 986 fold to homogeneity with the specific activity of 286 units/mg. AgpC hydrolyzed a wide variety of phosphorylated compounds with high activity for glucose-1-phosphate and glucose-6-phosphate. The optimum pH and temperature for the enzyme activity was pH 5.0 and 45 degrees C, respectively. The Km value for glucose-1-phosphate was 5.12 mM with a Vmax 27.8 U mg(-1). Its molecular weight was 46 kDa by SDS-PAGE gel and the sequence of N-terminal amino acid residues identified was Gln-Thr-Ala-Pro-Glu-Gly-Tyr-Gln-Leu-Gln. The glucose-1-phosphatase gene (agpC) was cloned from the C. braakii genomic library. This gene comprised 1,242 nucleotides and encoded a polypeptide of 413 amino acids. The result of its BLAST search showed a significant similarity with glucose-1-phosphatase from enterobacteria such as E. coli, Enterobacter, Shigella, and Salmonella.
Kim
Young-Ok
YO
Biotechnology Research Division, National Fisheries Research and Development Institute, 408-1, Gijang, Busan 619-902, South Korea. yobest12@korea.kr
Kim
Han-Woo
HW
Park
In-Suk
IS
Lee
Jeong-Ho
JH
Lee
Sang-Jun
SJ
Kim
Kyung-Kil
KK
D000595:Amino Acid Sequence; D002954:Citrobacter / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D003001:Cloning, Molecular; D004151:Dipeptides / Q000032:analysis*; D005958:Glucosephosphates / Q000032:analysis*; D008969:Molecular Sequence Data; D010446:Peptide Fragments; D010802:Phylogeny; D011487:Protein Conformation
D004151:Dipeptides; D005958:Glucosephosphates; D010446:Peptide Fragments; C038123:alanylproline; C035645:prolylglutamic acid; C031590:glucose-1-phosphate