Table 1.

Primer sets used to amplify genes encoding total bacteria 16S rRNA, FTHFS, mcrA, and ACS in this study

Target	Direction	Primer sequence (5'→3')	Reference
Total bacteria	F	CGGCAACGAGCGCAACCC	Denman and McSweeney, 2006
	R	CCATTGTAGCACGTGTGTAGCC
FTHFS	F	GTWTGGGCWAARGGYGGMGAAGG	Xu et al., 2009
	R	GARGAYGGWTTTGAYATYAC
mcrA	F	TTCGGTGGATCDCARAGRGC	Denman et al., 2007
	R	GBARGTCGWAWCCGTAGAATCC
ACS	F	CTBTGYGGDGCIGTIWSMTGG	Gagen et al., 2010
	R	AARCAWCCRCADGADGTCATIGG

F: forward; R: reverse; FTHFS: formyltetrahydrofolate synthetase; mcrA: methyl coenzyme-M reductase A; ACS: acetyl-CoA synthase