TABLE 3.

Antibody specificity for LPS core serogroups of Sinorhizobium spp.^a

LPS core serogroup	Immunoblot response of LPSb	MAb(s) or antiserumc	Sinorhizobium strains
Serogroup Ad	+	MAbs 10 and 11	S. meliloti strains (Rm41, Rm1021, NRG34, NRG133, NRG185, and NRG247) and S. fredii strains (USDA192, USDA196, USDA197, USDA201, USDA257, and HH103)
	+	Anti-Rm41
	−	Anti-Rf205
Serogroup B	−	MAbs 10 and 11	S. fredii USDA191, S. fredii USDA205, S. fredii USDA208, and Sinorhizobium sp. strain NGR234
	−	Anti-Rm41
	+	Anti-Rf205
Serogroup C	+/−	MAb 10	S. meliloti NRG23, S. meliloti NRG53, and S. meliloti NRG286
	−	MAb 11
	+/−	Anti-Rm41
	−	Anti-Rf205
Untyped	−	All MAbs and antisera	S. fredii HH303, S. meliloti NRG43, S. meliloti NRG282, and S. meliloti NRG289

^aThe LPS serogroup designations are a result of this study and have not been used previously. 

^bBased on degree of reaction with the R-LPS (Fig. 1). Symbols: +, positive; +/−, marginal; −, negative. 

^cSpecificity was determined by immunoblot analyses performed with MAb 10 and MAb 11 (Table 2) in this study or with polyclonal antisera in a earlier report (16). Anti-Rm41, polyclonal antiserum raised against whole cells of S. meliloti Rm41; Anti-Rf205, polyclonal antiserum raised against whole cells of S. fredii USDA205. 

^dSerogroup A also contains 49 other strains of S. meliloti, as shown by a positive response to untreated cells in the ELISAs performed by Olsen et al. (11) (see Table 3 in reference 11).