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Aldehyde dehydrogenase (Aldehyde Dehydrogenase, ALDH) is a superfamily widespread in bacteria, plants, animals and insects, a member of the superfamily can catalyze a variety of endogenous and exogenous aldehyde in the presence of NAD (P) generates the corresponding carboxylic acid. Aldehyde dehydrogenase in vivo to perform a variety of functions, such as participation in cell detoxification, metabolism and penetration protection. ALDH7 aldehyde dehydrogenase superfamily, a family among its members, an amino acid sequence having a high degree of similarity among different species, in order to reflect the \Arabidopsis Antiquitin (ALDH7B4) by the AT1G54100 gene loci located on chromosome 1 coding, its expression is regulated by dehydration, salt stress and ABA. Carried out in order to elucidate the biological function of Arabidopsis Antiquitin This thesis study as follows: 1. Arabidopsis Antiquitin gene recombined into the prokaryotic expression vector of pMAL-c4x and pET-41a, and inducible expression of T7 Express strains. 2 fusion protein in a soluble form, mainly accounted for 39.4% and 25.1% of the total cellular protein expression levels. Fusion proteins obtained by the the Amylose Resin affinity chromatography column and the Ni-NTA Protein Purification System. Acetaldehyde and NAD Determination of substrate fusion protein activity, the results show that the His-tag fusion with aldehyde dehydrogenase activity Antiquitin the specific activity 8.98U/mg, pH9.5, 30 ℃, the apparent Km and Vmax values ??were 1.08mM and 13.17U/mg. 4 Arabidopsis Antiquitin. Bioinformatic analysis of the system. Hydrophobicity analysis results show that the protein obvious transmembrane signal region. Multiple sequence alignment of Arabidopsis and pea Antiquitin sequence similarity of 79%, with the the people Antiquitin sequence similarity of 59%, and 61% with the snapper Antiquitin sequence similarity. The expression pattern analysis, Antiquitin expression in the roots, seeds, pollen, guard cells and mesophyll cells and tissues. Biotic and abiotic stress, Antiquitin expression in plants increased significantly. 5 by using the homology modeling obtain Arabidopsis Antiquitin space structure, the results show that the protein catalytic domain typical contains Antiquitin family protein, NADH binding domain and oligomerization domain, active site residues Gly238, Gly291 , Glu391, Phe393. The research carried out for the final plant Antiquitin biochemical functions clarify laid the foundation.
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