Table 3. Sequence variation of the seven loci used for MLSA in Planktothrix strains.

Locus	bp	N	Max. dissimilarity (%)	Number of variable sites	Number of alleles
All strains
16S rRNA	301	138	1.99	7	4
16S-ITS	312	138	8.2	32	8
PC-IGS	204	138	12.8	37	13
PSA-IGS	548	138	8.8	55	7
RNaseP	299	138	7.5	28(+56)a	13
rbcLX	336	138	5.9	42	7
rpoC	492	138	11.6	73	14
Average (±s.e.)			8.1±3.6b	39±8b	9.4±1.5b
Strains containing the mcy gene cluster
16S rRNA	301	82	0	0	1
16S-ITS	312	82	2.6	11	3
PC-IGS	204	82	6.9	20	11
PSA-IGS	548	82	3.5	20	5
RNaseP	241	82	1.7	8	8
rbcLX	336	82	4.3	31	6
rpoC	492	82	5.1	31	9
Average (±s.e.)			3.4±2.3c	17±4b,c	6.1±1.3b,c
Subgroup active in MC synthesis
16S rRNA	301	63	0	0	1
16S-ITS	312	63	2.3	10	2
PC-IGS	204	63	6.9	20	10
PSA-IGS	548	63	3.5	20	5
RNaseP	241	63	1.2	7	5
rbcLX	336	63	3.7	27	5
rpoC	492	63	4.9	31	8
Average (±s.e.)			3.2±2.3c	16±4b,c	5.1±1.2b,c
Subgroup inactive in MC synthesis
16S rRNA	301	19	0	0	1
16S-ITS	312	19	0.3	1	2
PC-IGS	203	19	6.9	14	3
PSA-IGS	548	19	3.3	18	3
RNaseP	241	19	1.2	3	3
rbcLX	336	19	1.8	13	3
rpoC	492	19	5.1	27	4
Average (±s.e.)			2.7±2.6c	11±4c	2.7±0.4c
Strains lacking the mcy gene cluster
16S rRNA	301	56	1.99	7	4
16S-ITS	312	56	8.2	32	6
PC-IGS	204	56	12.8	30	5
PSA-IGS	548	56	8.8	48	4
RNaseP	299	56	7.5	23(+56)a	7
rbcLX	336	56	5.9	34	4
rpoC	492	56	11	60	6
Average (±s.e.)			8.0±3.5b	33±6b,c	5.1±0.5b,c

Abbreviations: IGS, intergenic spacer region; MC, microcystin; MLSA, Multi Locus Sequence Analysis; PC, phycocyanin.

^a(Plus insertions).

^b,cIdentical superscripts mark groups that are not significantly different at P<0.05 (Tukey's post-hoc test).