TABLE 2.

AI-2-regulated genes (TCPSAM analysis)a

GenecDescriptionFold change in expressionb
SMU.96Putative DNA-directed RNA polymerase, delta subunit, rpoE 147.42
SMU.234Threonine dehydratase, livA 8.21
SMU.203230S ribosomal protein S2, rs24.40
SMU.1665*Putative branched-chain amino acid ABC transporter, ATP-binding protein, livF 4.04
SMU.2020*50S ribosomal protein L16, rl163.86
SMU.1168*Putative transcriptional regulator3.39
SMU.2001DNA-directed RNA polymerase, alpha subunit, rpoA 3.33
SMU.1816cPutative maturase-related protein3.07
SMU.848Conserved hypothetical protein3.06
SMU.188c Putative 33-kDa chaperonin (heat shock protein 33)3.00
SMU.35830S ribosomal protein S72.98
SMU.200330S ribosomal protein S13, rs132.80
SMU.05Conserved hypothetical protein2.79
SMU.2026c30S ribosomal protein S102.79
SMU.1667*Putative branched-chain amino acid ABC transporter, permease protein, livM 2.77
SMU.185830S ribosomal protein S18, rs182.67
SMU.200230S ribosomal protein S11, rs112.63
SMU.1615cConserved hypothetical protein2.55
SMU.200050S ribosomal protein L17, rl172.48
SMU.103*Putative PTS system, IIA component2.46
SMU.958Hypothetical protein2.41
SMU.361Phosphoglycerate kinase, pgk 2.36
SMU.201650S ribosomal protein L24, rl242.27
SMU.186030S ribosomal protein S6, rs62.26
SMU.200850S ribosomal protein L30, rl302.24
SMU.697Putative translation initiation factor IF32.19
SMU.200930S ribosomal protein S5, rs52.16
SMU.990*Putative dihydrodipicolinate synthase, dapA 2.12
SMU.2153c Putative peptidase2.08
SMU.1955*Putative cochaperonin GroES, groES 2.06
SMU.741Conserved hypothetical protein2.06
SMU.201430S ribosomal protein S14, rs142.05
SMU.357 30S ribosomal protein S122.01
SMU.1511cPutative acetyltransferase−2.02
SMU.750c Hypothetical protein−2.11
  • a Thirty-five genes were found to have significantly changed expression in the luxS mutant complemented with AI-1 from those in the luxS mutant without AI-2 (cutoff for the n-fold change of expression of 2.0, Δ = 0.25; rate of false positives, 0.8 per 100 genes).

  • b Average n-fold change in expression for up to six technical replicates.

  • c Asterisks indicate genes in which AI-2 restored the wild-type level of expression. Genes displayed in bold were also detected in the density-dependent analysis (see Table 1).