title: Proteomic identification of alpha-amylase isoforms encoded by RAmy3B/3C from germinating rice seeds.
abstract: We isolated and identified 10 alpha-amylase isoforms by using beta-cyclodextrin Sepharose affinity column chromatography and two-dimensional polyacrylamide gel electrophoresis from germinating rice (Oryza sativa L.) seeds. Immunoblots with anti-alpha-amylase I-1 and II-4 antibodies indicated that 8 isoforms in 10 are distinguishable from alpha-amylase I-1 and II-4. Peptide mass fingerprinting analysis showed that there exist novel isoforms encoded by RAmy3B and RAmy3C genes. The optimum temperature for enzyme reaction of the RAmy3B and RAmy3C coding isoforms resembled that of alpha-amylase isoform II-4 (RAmy3D). Furthermore, complex protein polymorphism resulted from a single alpha-amylase gene was found to occur not only in RAmy3D, but also in RAmy3B.
authors.affiliation: Graduate School of Science and Technology, Niigata University, Niigata, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Nanjo
authors.forename: Satoru
authors.initials: S
authors.lastname: Asatsuma
authors.forename: Kimiko
authors.initials: K
authors.lastname: Itoh
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Hori
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Mitsui
mesh_terms: D000595:Amino Acid Sequence; D002846:Chromatography, Affinity / Q000379:methods; D017343:Genes, Plant; D018525:Germination; D007527:Isoenzymes; D008969:Molecular Sequence Data; D012275:Oryza / Q000201:enzymology* / Q000235:genetics; D011110:Polymorphism, Genetic; D040901:Proteomics / Q000379:methods*; D012639:Seeds / Q000201:enzymology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D013696:Temperature; D000516:alpha-Amylases / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D007527:Isoenzymes; D000516:alpha-Amylases