Table 1.

Metadata of different environmental samples obtained from public databases

Sample	Biomes	Sampling location/region	Description	Database	Accession number	Total number of reads	DNA extraction kit/method	Sequencing platform	Reference
ARP 1 ARP 2 ARP 3	Amazon River plume	Western tropical North Atlantic Ocean	Samples were collected at Amazon River plume	NCBI_SRA	SRR1185414 SRR1186214 SRR1199271	1,724,868 1,304,682 1,277,913	Method proposed by [54]	Illumina Genome Analyzer IIx	[55, 56]
KR 1 KR 2 KR 3	Kalamas River	Epirus region of Greece	Samples were collected from the Kalamas River	NCBI_SRA	SRR3098756 SRR3098759 SRR3098769	10,792,071 7,698,589 5,351,255	Mo Bio Power Soil Kit (Mo Bio Inc. Carlsbad, CA, USA)	Illumina HiSeq 2500	[57]
DF 1 DF 2 DF 3	Dairy farm effluent	Cambridge, UK	Samples were collected from the effluent lagoon of a dairy farm	EMBL-EBI	ERR1193297 ERR1193298 ERR1193301	23,154,788 82,819,396 26,421,627	Meta-G-Nome DNA Isolation Kit, Epicentre)	Illumina HiSeq 2000	[19]
HE 1 HE 2 HE 3	Hospital effluent	Cambridge, UK	Samples were collected from the combined wastewater effluents of the main wards of university hospital	EMBL-EBI	ERR1191817 ERR1191818 ERR1191819	30,295,299 22,689,323 50,303,545
CR 1 CR 2 CR 3	Cam River	Cambridge, UK	Samples were collected within the River Cam catchment	EMBL-EBI	ERR1193292 ERR1193293 ERR1193294	17,899,008 68,902,092 43,078,304
HE 4	Hospital effluent	Singapore	Sample was collected from general ward	NCBI-SRA	SRR5997540	2,257,389	PowerWater DNA Isolation Kit (Mo Bio Lab, Inc, CA)	Illumina HiSeq 2500	[58]
HE 5 HE 6	Hospital effluent	Singapore	Samples were collected from clinical isolation ward	NCBI-SRA	SRR5997541 SRR5997548	1,927,227 2,090,859