. 2019 Apr 3;9(2):32. doi: 10.3390/life9020032

Table 5.

Flavodiiron proteins in heterocysts.

Family	Group	Subunit	Protein	Cofactor(s)	Metal ^†
Class-C flavodiiron proteins	Type 3	Flavodiiron protein (flavoprotein)	Flv1B (All0177 ^§)	Non-heme Fe–Fe center	2 Fe
				NAD(P)H ^‡	–
				FMN	–
	Type 1	Flavodiiron protein (flavoprotein)	Flv3B (All0178 ^§)	Non-heme Fe–Fe center	2 Fe
				NAD(P)H ^‡	–
				FMN	–

^† Charge is not given for Fe as it varies with the oxidation state during electron transfer. ^‡ Heterocyst-specific flavodiiron proteins might use ferredoxin [257]. ^§ Proteins in Anabaena sp. PCC 7120 [330].