Table 1.

List of the oligonucleotide primers utilized in this study.

Primer		Sequence (5′-3′)2	Specificity	Techniques	Reference
Taxonomic lineage	Name of primer
Bacteria	27F1	AGAGTTTGATCCTGGCTCAG	V1, 16S rDNA	PCR	[63]
	1492R1	GGTTACCTTGTTACGACTT	V9, 16S rDNA	PCR	[63]
	GC-338F	ACTCCTACGGGAGG CAGCAG	16S rDNA	PCR, DGGE	[19]
	518R	ATTACCGCGGCTGCTGG	16S rDNA	PCR, DGGE	[19]
	GC-948F	AACGCGGAAGAACCTTAC	V6, 16S rDNA	PCR, DGGE	[39]
	L1401R	CGGTGTGTACAAGAAGACCC	V8, 16S rDNA	PCR, DGGE	[63]
	GC-rpoB1698F3	AACATCGGTTTGATCAAC	rpoB	PCR, DGGE	[24]
	rpoB2041R	CGTTGCATGTTGGTACCCAT	rpoB	PCR, DGGE	[24]
Fungi	F3F	TCCTCTAAATGACCAAGTTTG	18S rRNA	PCR	[13]
	EF4R	GGAAGGG[G/A]TGTATTTATTAG	18S rRNA	PCR	[13]
Archaea	Arc 21F	TTCCGGTTGATCCYGCCGGA	16S rRNA	PCR	[64]
	Arc 958R	YCCGGCGTTGAMTCCAATT	16S rRNA	PCR	[64]
Eukarya	Euk1427F	TCTGTGATGCCCTTAGATGTTCTGGG	18S rRNA	PCR	[65]
	Euk1616R	GCGGTGTGTACAAAGGGCAGGG	18S rRNA	PCR	[65]

¹F: forward primer; R: reverse primer. The numbering denotes positions of primers relative to the E. coli 16S rDNA gene.

²GC clamp added to the 5′ end of the primer 338, 5′CGCCCGCCGCGCGCGGCGGGCGGGGCGGGGGCACGGGGG G 3′.

Sequences represent the nucleotide sequences in the GC clamps of the respective primers.