TABLE 3.

Numbers of genes with known or predicted functions that were significantlya up- or downregulated in acid-adapted L. casei ATCC 334b

General functional categoryAA-5AA-20AA20-AC
UpregulatedDownregulatedUpregulatedDownregulatedUpregulatedDownregulated
Metabolism
    Energy production, conversion113211
    Carbohydrate transport, metabolismc112923
    Amino acid transport, metabolism19512
    Nucleotide transport, metabolism42514
    Coenzyme metabolism11
    Secondary metabolites biosynthesis, transport, catabolism51
Information storage, processing
    Translation, ribosomal structure, biogenesis2583
    Transcription313
    DNA replication, recombination, repair52
    Mobile DNA elements1211
Cellular processes
    Protein turnover, stress response21133
    Signal transduction21
    Cell secretion72
    Cell envelope biogenesis1112
    Cell division, chromosome partitioning271
Poorly characterized, general function prediction only132527
  • a P < 0.05.

  • b Versus control cells grown at pH 6.0. AA5 or AA20, cells grown at pH 6.0 and then acid adapted for 5 or 20 min, respectively, in fresh MRS adjusted to pH 4.5; AA20-AC, cells grown at pH 6.0, incubated for 20 min in MRS adjusted to pH 4.5, and then suspended in MRS at pH 2.0 for 10 min. See Table S1 in the supplemental material for full details.

  • c —, no gene found.