Table 4. Primer used for direct PCR.

Gene	Premier	Nucleotide sequence(5′–3′)	fragment length(bp)
TcdA	NK1	GGACATGGTAAAGATGAATTC	546
	NK2	CCCAATAGAAGATTCAATATTAAGCTT
TcdB	NK104	GTGTAGCAATGAAAGTCCAAGTTTACGC	204
	NK105	CACTTAGCTCTTTGATTGCTGCACCT
Triose phosphate isomerase(tpi)	tpi-F	AAAGAAGCTACTAAGGGTACAAA	230
	tpi-R	CATAATATTGGGTCTATTCCTAC
16SrRNA	B	CCGTCAATTCMTTTRAGTTT*	270
	PG-48	CTCTTGAAACTGGGAGACTTG

^*M = A or C; R = A or G.