Table 1. Deduced functions of the ORFs in the echinomycin biosynthetic gene cluster from S. griseovariabilis and nucleotide sequence alignment with echinomycin biosynthetic gene cluster from S. lasaliensis and triostin A biosynthetic gene cluster from S. triostinicus.

Gene	Amino acids	Deduced function	S. lasaliensis homolog	S. triostinicus homolog
qui1 (partial)	50	ABC transporter	−	trsD (95%)
qui2	275	ABC transporter	−	trsE (96%)
qui3	402	Esterase	ecm14 (75%)	trsF (95%)
qui4	177	DNA-binding response regulator	ecm9 (81%)	trsG (98%)
qui5	71	MbtH-like protein	ecm8 (86%)	trsH (97%)
qui6	3146	Non-ribosomal peptide synthetase	ecm7 (81%)	trsI (93%)
qui7	2665	Non-ribosomal peptide synthetase	ecm6 (86%)	trsJ (95%)
qui8	233	SAM-dependent methyltransferase	ecm18 (75%)	trsK (95%)
qui9	427	Hypothetical protein	Not annotated (75%)	trsL (94%)
qui10	793	UvrA-like protein	ecm16 (87%)	trsM (97%)
qui11	313	Thioredoxin reductase	ecm17 (77%)	trsN (94%)
qui12	463	FAD-dependent oxidoreductase	ecm4 (79%)	trsO (95%)
qui13	363	Isopropylmalate dehydrogenase	ecm3 (82%)	trsP (94%)
qui14	249	Thioesterase	ecm2 (77%)	trsQ (97%)
qui15	402	Cytochrome P450 hydroxylase	ecm12 (76%)	trsB (97%)
qui16	528	AMP-binding ligase	ecm1 (83%)	trsA (95%)
qui17	275	Tryptophan 2,3-dioxygenase	ecm11 (very low)	trsC (95%)
qui18	611	Non-ribosomal peptide synthetase	ecm13 (73%)	trsR (96%)

The sequence of qui1 wasn’t complete, so it is labeled ‘partial’. The last two columns reveals the identity at nucleotide level of genes in the cluster of S. griseovariabilis to the homologs in S. lasaliensis and S. triostinicus. The number in the bracket denotes the identity; ‘−’ means no homologous gene was found, ‘very low’ means the putative homologous gene doesn’t have obvious identity, but is still considered homologous because of the amino acid identity of 46%.