Table 1

Attenuated mutants identified by IVASS

PESTDomain 1Domain 2Domain 3Domain 4 N-terminal region
LLO mutantaBlood plate phenotypebLLO mutantBlood plate phenotypeLLO mutantBlood plate phenotypeLLO mutantBlood plate phenotypeLLO mutantBlood plate phenotype
S44A+I61AY98AI204AcI421A+
P45A+D62AY406AoY206AY427Ao
A47G+I65AT409AQ216AN432Ao
P49A+N119AK220A
K50A+Y126AF221A
P52A+L145AG222A
K55AR149AF225A
D157AN229A
K175AV234A
L185AF236A
W189AG237A
Y197AI239A
Y255AV248A
Y256AF251A
N261AQ253A
F269AY303A
F270AA318G
L279AF319A
Y292AI337A
Y298AI338A
G299AK344A
G349Ao
G350A
I359A+
A374GWT
R378A
  • a Avirulent mutants were not detected in the livers and spleens of mice 48 h postinfection.

  • b Qualitative hemolysis activity was tested by streaking the individual mutant strains on sheep blood agar plates and comparing zones of hemolysis with those of wild-type bacteria. The activities are reported as follows: +, hyperhemolytic; −, hypohemolytic; o, ahemolytic. WT, wild type.

  • c Phenotype after extended incubation (8 to 9 days).