Bacteriophage tailspike protein based assay to monitor phase variable glucosylations in Salmonella O-antigens

BMC Microbiology

Table 1 Monoisotopic calculated and experimental mass analyses from MALDI-MS of two repeat unit (2RU) oligosaccharides obtained from O-antigen polysaccharide enzymatic cleavage with 9NATSP

Oligosaccharide composition^a	[M + Na]⁺ _calc/Da	[M + Na]⁺ _exp/Da
		Salmonella strain
		Heidelberg 586	Brancaster	Paratyphi B
2 RU	1241.45	1241.45	1241.44	1241.44
2 RU + 2Glc–Abe^b	1435.41	n.d. ^c	1435.47	1435.44
2 RU + 2Glc	1565.56	n.d. ^c	1565.53	1565.52
2 RU + 2Glc + Ac	1607.57	n.d. ^c	1607.53	1607.52

^atwo repeat units of basic repeat α-d-Galp-1-2-α-d-Manp(−α-3-1-Abep)-1-4-α-l-Rhap-1-3- as produced by TSP cleavage [44], Abe: Abequose, Ac: Acetylation
^bwithout Abequose
^cnot detected

ISSN: 1471-2180