Min K H, Sasaki S F, Kashiwabara Y, Suzuki H, Nisizawa K
J Biochem. 1977 Mar;81(3):539-46. doi: 10.1093/oxfordjournals.jbchem.a131488.
A lyophilized alginate lyase preparation obtained from dialyzed extract of sonicated Pseudomonas sp. cells was fractionated by gell filtration on a Sephadex G-150 column, and three alginate lyase [EC4.2.2.3] fractions, peaks I, II, and III, were obtained. They were remarkably thermolabile. The lyase fractions degraded two kinds of alginate fragments, a polygluuronide (SG), and a polyuronide consisting of both mannuronic and guluronic acid residues (SMG), as well as commerical alginate, but were virtually inactive toward polymannuronide fragment (SM). The modes of degradation of these substrates by the lyase fractions were endowise with different degrees of randomness. Attack by the peak I fraction was more random than those by peaks II and III. The main lysis products formed from SG and SMG by these layses were identified as mixtures of unsaturated tri- and monouronides. The unsaturated triuronide from SG was deltatugg and SMG yielded a mixture of deltaUGG and a poorly characterized unsaturated trimer, possibly deltaUMG. However, the patterns of monomer and trimer production by theselyase fractions changed in different ways during incubation.
从经超声处理的假单胞菌属细胞的透析提取物中获得的冻干海藻酸裂合酶制剂，通过在Sephadex G - 150柱上进行凝胶过滤进行分级分离，得到了三个海藻酸裂合酶[EC4.2.2.3]级分，即峰I、峰II和峰III。它们的热稳定性很差。这些裂合酶级分能降解两种海藻酸片段，一种是聚古洛糖醛酸（SG），另一种是由甘露糖醛酸和古洛糖醛酸残基组成的聚糖醛酸（SMG），以及商业海藻酸盐，但对聚甘露糖醛酸片段（SM）几乎没有活性。这些裂合酶级分对这些底物的降解方式在不同程度上具有随机性。峰I级分的攻击比峰II和峰III的攻击更具随机性。这些裂合酶作用于SG和SMG形成的主要裂解产物被鉴定为不饱和三糖醛酸和单糖醛酸的混合物。来自SG的不饱和三糖醛酸是δtugg，SMG产生了δUGG和一种特征不明确的不饱和三聚体（可能是δUMG）的混合物。然而，在孵育过程中，这些裂合酶级分产生单体和三聚体的模式以不同方式发生变化。
