Pyridoxal Kinase (PLK) is the key enzyme in VB6 metabolism. The crude solution of PLK enzyme was directly extracted from tea plant, after depositing and dialysing with ammonia sulfate by using the phenylhydrazine derivative method to assay the activity of the PLK and its properties. Results showed that the addition of 100%(m/m) PVPP of the fresh tea leaves extraction the PLK could get the best results. The purified tea PLK was enriched by 4.0 fold and its specific activity was 0.737 nmol/(min·mg protein). The requirement of divalent ion for catalysis was mandatory, Zn2+ was the most efficient ion for catalysis; the optimum temperature and pH of the enzyme were 60℃ and 6.0, respectively. Under optimal conditions, the Km values for pyridoxal and its reactive substrate ATP were 19.3 μmol/L and 53 μmol/L.
NIU Tian-tian
,
ZHANG Jian-yun
,
HUANG Long-quan
. Analysis on the Activity of Tea Pyridoxal Kinase[J]. Journal of Tea Science, 2010
, 30(4)
: 269
-272
.
DOI: 10.13305/j.cnki.jts.2010.04.006
[1] Kerry J A, Kroc F.Purification and characterization of pyridoxal kinase from human erythrocytes[J]. Preparative Biochemistry, 1986, 16(3): 199-216.
[2] Rohmer M, Konini M, Simonin P, et al. Isoprenoid biosynthesis in bacteria: A novel pathway for the early steps leading to isopentenyl diphosphate[J]. Biochemical Journal, 1993(295): 517-524.
[3] Tae Hiralawa-Sakurai, Kiyoshi Ohkawa, Makoto Matsuda.Purification and properties of pyridoxal kinase from bovine brain[J]. Molecular and Cellular Biochemistry, 1993(119): 203-207.
[4] Francis Kwok, Jprge E, Churchich. Brain Pyridoxal Kinase[J]. The Journal of Biological Chemistry, 1979(254): 6489-6495.
[5] Lum H K, Kwok F, Lo S.Cloning and characterization of Arabidopsis thaliana pyridoxal kinase[J]. Planta, 2002(215): 870-879.
[6] Churchich J E, Scholz G, Kwok F.Modulation of the catalytic activity of pyridoxal kinase bymetallothionein[J]. Biochem Int, 1988(17): 395-403.
[7] Churchich J E, Scholz G, Kwok F.Activation of pyridoxal kinase by metallothionein[J]. Biochi-mesty Biophys Acta, 1989(996): 181-186.
[8] Bradford M M A. Rapid and sensitive method for the quantitation of microgram of protein utilizing the principle of protein-dye binding[J]. Anal Biochem, 1976(72): 248-254.
[9] Huroshi Wada, Esmoda E Snell.The enzymatic oxidation of pyridoxine and pyridoxamine phosphates[J].The Journal of Biological Chemistry, 1961, 236(7): 2089-2095.
[10] Tagaya M, Yamano K, Fukui T.Kinetic studies of the pyridoxal kinase from pig liver: Slow-binding inhibition by adenosine tetra phosphate pyridoxal[J]. Biochemistry, 1989(28): 4670-4675.
[11] Lind berg AS, Leklem JE, Miller LT. The effect of wheat bran on the bioavailability of vitamin B6 in young men[J]. Nutr, 1983(113): 2578-2586.
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