The kinetic data were

fitted see more to the Michaelis-Menten equation by a non-linear least square regression method. The calculations and JAK inhibitor graphic results were generated by Prism 3.03 software. The catalytic constant k cat = Vmax/[E] (μmol s-1mg-1)/(mol mg-1). The molar concentrations of α-IPMS-2CR and α-IPMS-14CR were 1.426 × 10-8 and 1.084 × 10-8 moles/mg, respectively. Acknowledgements This work was supported by the National Center for Genetic Engineering and Biotechnology, Thailand. We thank Porntip Poolsawat for technical assistance. We also thank Dr. Vittaya Meewutsom, Microbiology Department, Mahidol University, for his help with the gel filtration experiment. Electronic supplementary material Additional file 1: Gel filtration profiles of α-IPMS-2CR. Gel filtration of α-IPMS-2CR. Material, Superdex 200 HR/30. A, B, C, D, E, F, and AZD0156 G (with arrows) refer to the peak positions of blue

dextran, amylase, alcohol dehydrogenase, BSA, carbonic anhydrase, cytochrome C, and vitamin B12. The major peak fractions was dimer protein and the minor peak fractions was tetramer protein. Enzyme activity of the minor peak fractions was approx. 1/3 of the major peak fractions. (PPT 77 KB) Additional file 2: Gel filtration profiles of α-IPMS-14CR. Gel filtration of α-IPMS-14CR. Material, Superdex 200 HR/30. A, B, C, D, E, F, and G (with arrows) refer to the peak positions of blue dextran, amylase, alcohol dehydrogenase, BSA, carbonic anhydrase, cytochrome C, and vitamin B12. The major peak fractions was dimer protein and the minor peak fractions was monomer protein. Enzyme activity of the minor peak fractions was approx. 1/6 of the major peak fractions. (PPT 78 KB) References 1. Stieglitz BI, Calco JM: Distribution of the isopropylmalate this website pathway to leucine among diverse bacteria. J Bacteriol 1974, 118:935–941.PubMed 2. Kohlaw GB, Leary TR: α-Isopropylmalate synthase from Salmonella typhimurium : purification and properties. J Biol Chem 1969, 244:2218–2225. 3. Wiegel J: α-Isopropylmalate synthase as a marker for the leucine biosynthesis pathway in several Clostridia and in Bacteroides fragilis. Arch Microbiol 1981, 130:385–390.PubMedCrossRef

4. Chanchaem W, Palittapongarnpim P: A variable number of tandem repeats result in polymorphic α-isopropylmalate synthase in Mycobacterium tuberculosis. Tuberculosis (Edinb) 2002, 81:1–6.CrossRef 5. Beltzer JP, Chang L, Hinkkaneen AE, Kohlhaw GB: Structure of yeast Leu4. J Biol Chem 1986, 261:5160–5167.PubMed 6. Webster RE, Gross SR: The α-isopropylmalate synthase of Neurospora . I. The kinetics and end product control of α-isopropylmalate synthase function. Biochemistry 1965, 4:2309–2318.CrossRef 7. de Kraker JW, Luck K, Textor S, Tokuhisa JG, Gershenzon J: Two Arabidopsis genes (IPMS1 and IPMS2) encode isopropylmalate synthase, the branchpoint step in the biosynthesis of leucine. Plant Physiol 2007, 143:970–86.PubMedCrossRef 8.