Nock L P, Mazelis M
Arch Biochem Biophys. 1986 Aug 15;249(1):27-33. doi: 10.1016/0003-9861(86)90556-4.
Alliin lyase from garlic (Allium sativum) has been purified to homogeneity. The purification procedure involves the use of affinity chromatography on concanavalin A-Sepharose 4B. Addition of polyvinylpolypyrrolidone to the homogenizing medium greatly improves the specific activity of the extract. The enzyme is a glycoprotein as seen by its ability to bind to concanavalin A-Sepharose 4B and by its positive periodic acid-Schiff base stain. It has a carbohydrate content of 5.5%. Km values for this enzyme were estimated to be 5.7 mM for S-ethyl-L-cysteine sulfoxide and 3.3 mM for S-allyl-L-cysteine sulfoxide. The molecular weight of this garlic enzyme, as determined by gel filtration, was found to be 85,000; the molecule consists of two equal subunits of Mr 42,000. The amino acid content was found to be similar to that reported previously for onion alliin lyase, although there is twice as much tryptophan in the garlic alliin lyase as in the onion enzyme. By both chemical and spectral methods the enzyme was found to have two molecules of pyridoxal 5-phosphate per enzyme molecule, suggesting one per subunit. There are significant differences in the nature of these findings from those previously reported from this laboratory for the onion enzyme. Studies are in progress to compare further the alliin lyases from garlic and onion.
大蒜（葱属植物）中的蒜氨酸裂解酶已被纯化至同质状态。纯化过程涉及使用伴刀豆球蛋白A - 琼脂糖4B进行亲和色谱法。在匀浆介质中添加聚乙烯聚吡咯烷酮可大大提高提取物的比活性。该酶是一种糖蛋白，这可从其与伴刀豆球蛋白A - 琼脂糖4B结合的能力以及其阳性过碘酸 - 席夫碱染色中看出。它的碳水化合物含量为5.5%。该酶对S - 乙基 - L - 半胱氨酸亚砜的Km值估计为5.7 mM，对S - 烯丙基 - L - 半胱氨酸亚砜的Km值为3.3 mM。通过凝胶过滤测定，这种大蒜酶的分子量为85,000；该分子由两个分子量为42,000的相等亚基组成。发现其氨基酸含量与先前报道的洋葱蒜氨酸裂解酶相似，尽管大蒜蒜氨酸裂解酶中的色氨酸含量是洋葱酶中的两倍。通过化学和光谱方法发现，每个酶分子含有两个磷酸吡哆醛分子，表明每个亚基一个。这些发现的性质与本实验室先前报道的洋葱酶的发现有显著差异。正在进行研究以进一步比较大蒜和洋葱中的蒜氨酸裂解酶。
