层理鞭枝藻的藻蓝蛋白和藻红蓝蛋白α-亚基及其色素肽的光化学与光谱性质

PHOTOCHEMICAL AND SPECTRAL PROPERTIES OF PHYCOCYANIN AND PHYCOERYTHROCYANIN α SUBUNIT AND THEIR CHROMOPEPTIDE FROM MASTIGOCLADUS LAMINOSUS

用紫外可见吸收和圆二色光谱研究了层理鞭枝藻的藻蓝蛋白α－亚基色素肽和藻红蓝蛋白α－亚基色素肽的可逆光化学，这些研究表明藻蓝蛋白α－亚基色素肽和藻红蓝蛋白α－亚基色素肽分别相应于藻蓝蛋白和藻红蓝蛋白的辅基色素结构域．藻蓝蛋白α－亚基色素肽的光谱性质和可逆光化学与藻蓝蛋白α－亚基的相应性质很相似，藻红蓝蛋白α－亚基色素肽的光谱性质和可逆光化学与藻红蓝蛋白α－亚基的相应性质相似，不过藻红蓝蛋白α－亚基色素肽还具有一种新的可逆光化学性质，本文中称为类型Ⅲ可逆光化学，藻红蓝蛋白α－亚基在１ｍｏｌ／Ｌ硫氰化钾和４ｍｏｌ／Ｌ尿素中也具有该类型Ⅲ可逆光化学．

Photochemical and spectral properties of phycocyanin and phycoerythrocyanin α subunit and their chromopeptide from Mastigocladus laminosus were studied by absorption and circular dichroism spectroscopy. From these studies, it is suggested that the phycocyanin and phycoerythrocyanin α subunit chromopeptide correspond to the chromophore structural domain of phycocyanin and phycoerythrocyanin α subunit, respectively. The photochemical and spectral properties of the phycocyanin and phycoerythrocyanin α subunit chromopeptide are similar to these of phycocyanin and phycoerythrocyanin α subunit, respectively. Type Ⅱ phycoerythrocyanin α subunit chromopeptide has a new reversible photochemistry, here called type Ⅲ reversible photochemistry, and type Ⅱ phycoerythrocyanin α subunit possesses this type Ⅲ reversible photochemistry only in the presence of 1 mol/L KSCN or 4 mol/L urea.