S. Otsuka et al., Phylogenetic relationships between toxic and non-toxic strains of the genus Microcystis based on 16S to 23S internal transcribed spacer sequence, FEMS MICROB, 172(1), 1999, pp. 15-21
16S to 23S ribosomal DNA internal transcribed spacer sequences of 47 strain
s of the genus Microcystis were determined. Derived maximum likelihood and
DNA distance trees indicated that Microcystis can be divided into three clu
sters. The first cluster included toxic and non-toxic strains, the second o
nly toxic ones, and the third only non-toxic ones. The tree topologies were
not necessarily correlated with morphospecies distinction or phycobilin pi
gment composition, and one genotype may have more than one morphotype. Phyl
ogenetic analysis based on intergenic spacer sequences was thought to be ef
fective for understanding relationships among closely related species and s
trains. (C) 1999 Federation of European Microbiological Societies. Publishe
d by Elsevier Science B.V. All rights reserved.