Illustration of four sequence types of the cyrI gene. (A) Schematic structures of cyrI sequence types. White bar, cyrI sequences; black and gray bars, repeat sequences; slash and backslash bar, insertion sequences; C. raciborskii AWT205, reference strain. (B) Partial alignment of representative cyrI gene sequences. Repeat sequences and insertion sequences were italicized. Dashed line, gaps introduced into the alignment; bold line, ITRs; arrow, beginning of the repeat sequences.  

Contexts in source publication

Context 1

... primer pair PCF/PCR (54) with specificity targeting the phy- cocyanin operon (cpc) of cyanobacteria was used to confirm the validity of DNA templates for PCRs. Primers specific for cyrA, cyrI, and cyrJ genes of current known CYN-producing species were designed (see Fig. S2A in the supplemental material). Another primer set, rpoC1F53/rpoC1R739, was designed to selectively amplify the rpoC1 genes of Cylindrospermopsis and Raphidiopsis (see Fig. S2B in the supplemental material). PCR mix were prepared in 50-l volumes containing 5 l of 10 PCR buffer (TaKaRa, Japan), 10 nmol of each deoxynucleotide ...

Context 2

... was used to confirm the validity of DNA templates for PCRs. Primers specific for cyrA, cyrI, and cyrJ genes of current known CYN-producing species were designed (see Fig. S2A in the supplemental material). Another primer set, rpoC1F53/rpoC1R739, was designed to selectively amplify the rpoC1 genes of Cylindrospermopsis and Raphidiopsis (see Fig. S2B in the supplemental material). PCR mix were prepared in 50-l volumes containing 5 l of 10 PCR buffer (TaKaRa, Japan), 10 nmol of each deoxynucleotide triphosphate, 10 pmol of each primer, 1 U of LA Taq (TaKaRa), and 100 ng of DNA templates. The cycling conditions were as follows: 94°C for 3 min; 35 cycles of 94°C for 45 s, 50°C to 60°C ...

Context 3

... similar mutations to the cyrI gene of C. raciborskii CHAB358. Base transversions from guanine to thymine at bp 304 of two sequences were observed and also formed stop codons. In addi- tion, four types of cyrI sequences were recognized according to intragenic sequence insertions compared to the cyrI gene of C. raciborskii AWT205, as depicted in Fig. 2. Itype1 contained no insertion sequence, but an insertion of a 6-nucleotide fragment, which is a repeat copy of its upstream sequence, was observed in Itype2 and Itype3 after bp 622. In addition, another insertion of a 30-nucleotide fragment, which is also a repeat copy of its up- stream sequence, was observed in Itype3 after bp 494. ...

Context 4

... cated at the C-terminal ends due to single-nucleotide deletions within the cyrK genes. However, the transcription of mutant cyrK and cyrI genes could still be detected. The transcription of cyrI genes may be ascribed to the cotranscription of polycistron (38), but cyrK gene was transcribed in the direction opposite to that of other cyr genes (Fig. 2). The release of CYNs in four strains with the CyrK of different lengths was investigated during a short cul- ture period. A minor proportion of the total CYNs were extracel- lular for each strain (15 to 40%), but the accumulation of extra- cellular CYNs during the exponential growth phase must result from active release as proposed by ...