TABLE 5

Discrepancies between SerotypeFinder predictions and the reported conventional results

IsolateSerotypeSerotypeFinder IDComment
RN587/1O157:H8H45Difficult to type according to authors (29)
W27aO115:K−:H18H19Original transcription error suspected; now the strain is nonmotile and cannot be confirmed; three of 116 motile O115 strains in the WHOCC database are H19, and none are H18
U19-41O51:K−:H24H49Original transcription error suspected; the isolate agglutinates only the H pool containing H49, and not the H pool containing H24
F7902-41O15:K14:H4H17Prediction based on fliC; H4 and H17 fliC are very similar in sequence; unresolved
53638O144O124:H30Suspected transcription error or typing mistake
178-54(1986-54)bO129:K−:H11O13/O135Re-tested and confirmed O129
C2139-99O111:H7O96Unresolved
F10524-41bO62:K−:H30O13/O135Isolate is still subjected to O-antigen testing, as the antigen is rough
F8858-41(O19a)cO133Suspected mix-up; the isolate was subjected to retyping of O antigen, and many cross-reactions occurred (O26, O50 and O133); final O-antigen determination was not possible
HW35O11:Kne:H33O99Suspected original transcription error; the isolate was confirmed as O99, with no cross-reaction with the O11 antisera
SE11O152:H28O173Unresolved
SSI_AA017O41:H48O60Unresolved; poor sequence data and assembly
SSI_AA037O20:K67:H17O128acThe O128 detected is suspected to be due to K67
SSI_AA099O43:H46O131Retesting confirmed O131
SSI_AA095O44:K53,93:H46O17Cross-reactions between O17, O44, O73, and O77 make it difficult to determine these O groups phenotypically; retesting confirmed O44
  • a The O115 reference strain was sequenced both at CDC and SSI with the same results in SerotypeFinder.

  • b Variant sequences for the reference strains for O129 [178-54(1986-54)] and O62 (F10524-41) were represented in the O database, and therefore, resequencing of these strains was not considered as part of the validation set.

  • c The parentheses indicate that final O-antigen determination was not possible.