Table 2.

Predicted binding pockets of the adenylation domain of McyA₂

Strain	Binding pocket										Score %(a)	Predicted(a)	Activated
	235	236	239	278	299	301	322	330	331	517
Anabaena sp. 90	D	L	F	N	N	A	L	T	Y	K	100	Ala	Ala
Microcystis aeruginosa NIES-843	-	-	-	-	-	-	-	-	-	-	100	Ala	Ala
Microcystis aeruginosa PCC7806	-	-	-	-	-	-	-	-	-	-	100	Ala	Ala
Microcystis aeruginosa UV027	-	-	-	-	-	-	-	-	-	-	100	Ala	Ala
Microcystis aeruginosa K-139	-	-	-	-	-	-	-	-	-	-	100	Ala	Ala
Nostoc sp. 152	-	-	-	-	-	-	-	-	-	-	100	Ala	Ala*
Phormidium sp. DVL1003c	-	-	-	-	-	-	-	-	-	-	100	Ala	Ala
Planktothrix rubescens NIVA-CYA 98	-	-	-	-	-	-	-	-	-	-	100	Ala	Ala
Planktothrix agardhii NIVA-CYA 126/8	-	-	-	-	-	-	-	S	-	-	90	Ala	Ala
Microcystis sp. RST 9501	-	-	-	-	-	G	-	I	C	-	70	Cys	Leu, Met
Microcystis aeruginosa NPLJ-4	-	-	-	-	-	G	-	I	C	-	70	Cys	Leu, Met ±
Nostoc sp. UK89IIa	-	A	W	F	L	G	N	V	V	-	100	Leu	Leu
Phormidium sp. CENA270	-	A	W	F	L	G	N	V	V	-	100	Leu	Leu

The adenylation domain of McyA₂ is responsible for amino acid activation in position one of microcystins.

(a) Prediction obtained using the NRPSpredictor2 program [72,73]. Trace amounts of *Serine and ± Valine or Phenylalanine detected in LC-MS/MS.