TABLE 6.

Primers used in this study

Target gene by type	Primer name	Gene description	Primer sequence (5′→3′)	Description of design (reference or accession no.)
Housekeeping
atpD	atpDF-SUT-PR48	ATP synthase subunit beta	TGTTGTCGACGAAGAACAGC	Designed from atpD of Bradyrhizobium sp. strain ORS285 (LT859959.1)
	atpDR-SUT-PR48		CACGAGTTCATCGAGTCCAA
	atpDF-SUTN9-2		TGTTGTCGACGAAGAACAGC	Designed from atpD of Bradyrhizobium sp. strain SUTN9-2 (LAXE00000000)
	atpDR-SUTN9-2		CACGAGTTCATCGAGTCCAA
Nitric oxide production
norB	norB F-SUT-PR48	Nitric oxide reductase	AAGACCACGGTGACCAACAT	Designed from norB of Bradyrhizobium sp. strain ORS285 (LT859959.1)
	norB R-SUT-PR48		CGATCGATACCGTTGAGCTT
	norBF-SUTN9-2		ACAGGAAGAAGATCGCAACG	Designed from norB of Bradyrhizobium sp. strain SUTN9-2 (LAXE00000000)
	norBR-SUTN9-2		GTGGCTGTGGTCGGTTATCT
nirK	nirK F-SUT-PR48	Cu-containing nitrite reductase	TGCTGATCGTCCATTCTCAG	Designed from nirK of Bradyrhizobium sp. strain ORS285 (LT859959.1)
	nirK R-SUT-PR48		TGTGGGTGACGTAAGCGTAG
	nirK F-SUTN9-2		TTGAAGTTGCCCTTCTCGTC	Designed from nirK of Bradyrhizobium sp. strain SUTN9-2 (LAXE00000000)
	nirK R-SUTN9-2		GGCGTGTTCGTGTATCACTG
Nitrogen fixation
nifH	nifH F	Dinitrogenase reductase	TACGGNAARGGSGGNATCGGCAA	Noisangiam et al. (62)
	nifH R		AGCATGTCYTCSAGYTCNTCCA
nifH-GUS (transcriptional fusion)
	nifHpm.SUTN9-2.F	nifH promoter region	ACCTATGTCGACGTGCTGAGCTGACTGAGTGG	Designed from nifH promoter region of Bradyrhizobium sp. strain SUTN9-2 (LAXE00000000)
	nifHpm.SUTN9-2.R		GCGTCGTCTAGAACTCAGCCCTCACTCAGTGT
	pVO.Bis.r	pVO155 plasmid	GCACAGCAATTGCCCGGCTTTCTTG	Designed from pVO155 plasmid (to confirm nifH-GUS integrated into SUTN9-2 chromosome)
	CefoM15-Fin.f	Cefotaxime gene	GCTATGGCACCACCAACGATATC	Designed from CefoM15 gene (to confirm nifH-GUS integrated into SUTN9-2 chromosome)