坛紫菜绿色突变体的分离与特性分析

Isolation and characterization of a green type mutant in Porphyra haitanensis Chang et Zheng(Bangiales,Rhodophyta)

野生型坛紫菜壳孢子苗经MNNG处理后,在它们的叶状体中,出现了许多色彩发生变异的细胞,大部分的变异细胞随后分裂形成块状的细胞块。用酶解法分离含绿色变异细胞块的叶状体的单离细胞,从细胞再生体中分离出一株绿色突变体。在叶状体活体吸收光谱特性方面,绿色突变体与野生型相比存在着明显的差异,3λmax和4λmax的峰顶分别向短波方向移动了约12 nm和3 nm。另外,绿色突变体的藻红蛋白和叶绿素a的含量下降,藻蓝蛋白的含量上升,表现出较低的PE/Chl.a和PE/PC比值,较高的PC/Chl.a比值。绿色突变体的生长和成熟均比野生型慢。

The young gametophytic blades of Porphyra haitanensis, developed from conchospores of the wild type, were treated with N-methyl-N ′-nitro-N-nitrosoguanidine （MNNG） for inducing mutations. The color-mutated blades, which consisted of purplish red, red orange, orange, yellow green, light yellow and other color-mutated cells, were obtained after the treatment. The single cells were isolated enzymatically from the mutated blades, and were regenerated into whole plants among where appeared single-colored mutant blades and variegated blades that spottedly consisted of color-mutated cells and the wild-type cells. A green mutant strain was obtained from a green single-colored mutant by parthenogenesis. The green mutant was relatively stable in color in both gametophytic blade and conchocelis phases. The blade of the green mutant showed characteristic difference in the in vivo absorption spectra, by showing quite lower 3X and quite higher 4λmax as compared with the wild type, （PE） and phycocyanin （PC） mostly contributes to the absorptions, respectively. And its 3λmax where phycoerythrin and 4λmax were shifted towards shorter wavelength by 12 nm and 3 nm, respectively. The green mutant showed differences in contents of chlorophyll a （Chl. a）, phycoerythrin （PE） and phycoeyanin （PC） as compared with the wild type. The green mutant is characterized with lower PE/Chl. a and PE/PC ratios, and higher PC/Chl. a ratio. The growth and maturation of the green mutant were relatively slower than the wild type.