TABLE 1.

Characterization of the mutantsa

Functional familyStrainGenePutative functionORF no.Mouse CILog CFU in HeLa cells/log CFU in macrophages
Transport19C3 macA Macrolide effluxBMEI03591.0 × 10−32.4 ± 0.1/2.4 ± 0.1
16H1 tig Trigger factorBMEI10694.0 × 10−32.2 ± 0.1/2.5 ± 0.4
9A12 ugpA Glycerol transportBMEII05911.1 × 10−21.8 ± 0.2/2.9 ± 1.1
17F2 ugpA Glycerol transportBMEII06243.5 × 10−32.5 ± 0.1/2.5 ± 0.1
Metabolism15B2 dppA Dipeptide uptakeBMEI04333.2 × 10−42.1 ± 0.4/3.3 ± 0.5
13D6 ilvC Val, Leu, and Ile synthesisBMEI06243.1 × 10−2ND/NDb
8C7 cobB Cobalamin synthesisBMEI07054.6 × 10−21.8 ± 0.2/3.3 ± 0.8
8A8 mosA Inosamine methylaseBMEI13013.3 × 10−21.7 ± 0.1/2.4 ± 0.6
16A11 galcD d-Galactarate dehydrataseBMEII04852.2 × 10−32.4 ± 0.1/3.0 ± 0.8
15H1 glcK Glycerol kinaseBMEII08233.3 × 10−22.3 ± 0.3/3.1 ± 0.2
Regulation13B1 asnC familyTranscriptional regulatorBMEI03575.4 × 10−40.9 ± 0.2/1.8 ± 0.2
16B12 feuQ SensorBMEI13368.0 × 10−42.4 ± 0.3/2.4 ± 0.1
16D3 gntR familyTranscriptional regulatorBMEII10661.0 × 10−12.4 ± 0.3/2.8 ± 0.1
DNA-RNA metabolism9A3 rpoA RNA polymeraseα -subunitBMEI07811.2 × 10−41.3 ± 0.1/0.5 ± 0.2
19A4 xseA ExodeoxyribonucleaseBMEII05273.7 × 10−31.2 ± 0.2/1.8 ± 0.3
LPS17F3 pmm Core biosynthesisBMEI13965.7 × 10−32.3 ± 0.3/2.2 ± 0.2
Flagella9C6 fliF MS ringBMEII01516.6 × 10−22.0 ± 0.3/2.6 ± 0.7
Oxidoreduction16B2 pheB Catechol dioxygenaseBMEII01363.2 × 10−4ND/ND
19A2 fdhA Formate dehydrogenaseBMEII03781.3 × 10−2ND/ND
14G4 norE Nitric oxide reductionBMEII10012.2 × 10−31.9 ± 0.1/2.5 ± 0.1
Unknown10B11Int. reg.Intergenic regionBMEI0330-I03314.8 × 10−51.7 ± 0.1/2.0 ± 0.1
9A4Hypothetical proteinCoenzyme A-transferase IIIBMEI08981.7 × 10−22.5 ± 0.6/2.0 ± 0.5
8B9Hypothetical proteinThioesteraseBMEI11672.5 × 10−22.5 ± 0.5/2.0 ± 0.2
15F3Hypothetical protein Brucella/Agrobacterium orphan geneBMEI12294.5 × 10−1ND/ND
14D3Hypothetical protein Brucella/Agrobacterium orphan geneBMEI13393.6 × 10−41.5 ± 0.1/3.3 ± 0.2
17E7Hypothetical proteinα-Proteobacteria orphan geneBMEI13618.5 × 10−4ND/ND
13G7Hypothetical proteinα-Proteobacteria orphan geneBMEI14333.2 × 10−41.9 ± 0.1/2.2 ± 0.1
14B12Hypothetical proteinEAL domainBMEI14484.5 × 10−32.8 ± 0.1/2.5 ± 0.5
14B5Hypothetical proteinTetratricopeptide repeat domainBMEI15313.0 × 10−22.9 ± 0.5/0.8 ± 0.2
17B2Hypothetical proteinERFK/YBIS/YCFS/YNHG familyBMEI18091.0 × 10−31.7 ± 0.2/2.8 ± 0.2
8B8Hypothetical protein Rhizobiaceae orphan geneBMEI18444.7 × 10−31.6 ± 0.4/2.0 ± 0.2
9H5Hypothetical protein Brucella/Mesorhizobium orphan geneBMEI18791.8 × 10−21.7 ± 0.2/2.0 ± 0.1
13G9Hypothetical proteinBeta-lactamaseBMEII03182.5 × 10−41.4 ± 0.2/2.4 ± 0.2
13C9Hypothetical proteinDipeptidase domainBMEII06267.8 × 10−42.8 ± 0.2/2.4 ± 0.5
8D7Hypothetical proteinTransmembrane proteinBMEII09351.7 × 10−21.9 ± 0.2/1.7 ± 0.2
17B1Hypothetical proteinHalo-acid hydrolase domainBMEII10451.3 × 10−22.6 ± 0.1/3.3 ± 0.4
  • a For each mutant, homology searches were undertaken, using transposon flanking sequences against the genome of B. melitensis. The ORF number for each identified gene is given, and the putative function is based on homologies found by searching the BLAST database for the protein sequence deduced from each ORF. For the ORFs encoding proteins of unknown function, the domains detected by pfam are given. CIs were calculated relative to the wild-type strain B. melitensis 16M. The CI is defined as the output ratio (mutant/wild type) divided by the input ratio (mutant/wild type). Mouse CIs are the averages of CIs determined for two mice. Attenuation in a cellular model at 48 h postinfection is expressed as the difference in the log CFU between the wild type and the mutant. The standard deviations indicated are based on the mutants; the standard deviation for the wild type was ±0.03 for the two cellular models tested. Cellular infections were done individually for each mutant, and the experiments were performed two times in triplicate, with a ratio of 300 bacteria/cell.

  • b ND, not done.