Table 1.
Number of study NTS isolates by serovar and origin.
Fig 1.
SBA results of STm and SEn isolates with Malawi serum pool.
Bacterial colony forming units (CFU) were counted at time 0 (T0) and after 3 h (T180) incubation of bacteria in 45 μL undiluted serum (final bacterial concentration 1×106 CFU/ml). Killing/growth was determined by Log10 (CFU at T180)-Log10 (CFU at T0). Strains that could grow (Log10 change >0) were considered “resistant”, strains that were killed (Log10 change <0) were considered susceptible. Dashed/continuous line indicates median Log10 change of STm (-2.9) and SEn (-1.2) isolates, respectively.
Fig 2.
OAg production of S. Typhimurium (STm) and S. Enteritidis (SEn) isolates after growth and normalization to the same final OD: 35.
Dashed/continuous line indicates median OAg production of S. Typhimurium (STm) (14.4 μg/ml/OD) and S. Enteritidis (SEn) (16.8 μg/ml/OD) isolates, respectively.
Fig 3.
a) HPLC-SEC profile of S. Typhimurium Ke212 OAg (similar profiles obtained for all NTS strains; b) 1H NMR of S. Enteritidis Ke189 OAg and c) S. Typhimurium Ke004 OAg (arrows indicate O-acetyl groups); d) HPAEC-PAD profile of S. Typhimurium Ke012 OAg sample indicating typical sugars of the repeating unit (Rha, Gal, Glc and Man) and of the core region (Gal, Glc and NAcGlc) (similar profiles obtained for all NTS strains).
Table 2.
Proportion distribution in percentages of O-acetylation and glucosylation levels among NTS isolates.
Fig 4.
Correlation of SBA results and OAg production levels in (a) S. Typhimurium isolates (p = 0.002) and (b) S. Enteritidis isolates (p = 0.637).
r is the Spearman correlation coefficient.
CI is confidence interval.
Fig 5.
Correlation of SBA results (a, c) and OAg production levels (b, d) in S. Typhimurium (a, b) and S. Enteritidis (c, d) isolates with clinical presentations.
Samples for which no clinical presentation was determined were excluded from analysis. Malawi serum pool was used for SBA. Invasive: Salmonella isolates from blood, urine, CSF. Gastrointestinal: Salmonella isolates from stools. Controls: Salmonella isolates from stools of healthy controls.
Fig 6.
Correlation of S. Typhimurium (STm) OAg production levels and glucosylation (p<0.0001).
r is the Spearman correlation coefficient.
CI is confidence interval.