Fluorogenic Membrane Overlays to Enumerate Total and Fecal Escherichia coli and Total Vibrionaceae in Shellfish and Seawater

Table 1

Escherichia coli isolates (non-O157:H7) used in this study and results of 4-methyl-𝛽-D-glucuronide (MUG) overlay for the detection of 𝛽-glucuronidase-producing bacteria, most probable number (MPN) assay in EC tubes containing MUG, and colony overlay procedure for peptidases (COPP) overlay for lysyl aminopeptidase activity.

Serotype	ID code	Source^1	No. MUG+ in triplicate overlays^2	MPN-MUG tubes^3
				Growth	Gas	MUG fluorescence
O4:NM	88.0545	USDA	3	+	+	±
O4:NM	90.2258	USDA	3	±	−	+
O4:NM	STEC	USDA	3	+	+	−
O5:NM	79.0396	USDA	3	+	+	±
O5:NM	84.0166	USDA	0	+	+	−
O5:NM	85.0587	USDA	3	+	+	±
O9:H21	83.0625	USDA	3	+	+	±
O14:NM	STEC	USDA	0	±	−	±
O22:H5	95-3322 STEC	USDA	3	+	+	+
O22:H8	90-0327	USDA	3	+	+	±
O26:H11	88.1457	USDA	3	+	+	−
O26:H11	90.0105	USDA	3	+	+	+
O26:H11	3359-70	USDA	3	+	+	±
O28ac:H-	CVD/EI-1	USDA	3	+	−	+
O28ac:H-	CVD/EI-2	USDA	0	+	−	−
O28ac:H-	CVD/EI-4	USDA	3	+	−	+
O29:NM	43982	ATCC	0	+	+	−
O38:H21	96-3307 CDC	USDA	3	+	+	+
O42:H2	88.0501	USDA	0	+	+	±
O44:H18	O42	USDA	3	+	+	+
O78:H11	35401	ATCC	3	+	−	−
O78:K80:H12	34896	ATCC	3	+	+	+
O91:H	3610606 Stx2	USDA	3	+	+	−
O91:H14	96.0348Stx1	USDA	3	+	+	−
O103:H2	87.1368	USDA	0	+	+	±
O103:H2	93.0626	USDA	3	+	+	±
O103:H2	97-3112 STEC	USDA	0	+	+	−
O103:H25	97-3112 CDC	USDA	0	+	+	−
O111:H-	JB1-95	USDA	0	+	−	−
O111:NM	91.1030	USDA	0	+	+	±
O128:H45	19-3305 CDC	USDA	0	+	+	−
O128:H45	96-3305 STEC	USDA	0	+	+	−
O137:H41	88-3493 CDC	USDA	3	+	+	+
O145:NM	83-75 STEC	USDA	3	+	+	+
O145:NM	87.1009	USDA	3	+	+	+
O157:NM	21902B	USDA	0	+	+	−
O:H4	06E01767	USDA	3	+	+	+

¹Abbreviations: ATCC: American Type Culture Collection, Manassas, Virginia; USDA: United States Department of Agriculture, Agricultural Research Service, Wyndmoor, Pennsylvania.
²MUG and COPP overlays were performed at 37^∘C.
³MPN-MUG assays were incubated at 44.5^∘C.