TABLE 2.
Changes in expression of the lag-phase proteins and genes in L. lactis subsp. lactis CNRZ 157 grown in synthetic medium as determined by 2D-PAGE and by microarraysa
| COG functional category and protein(s) | Protein induction (Lag/Stat) n-fold ± SDb | Gene induction (Lag/Stat) n-fold ± SDb |
|---|---|---|
| Nucleotide transport and metabolism | ||
| Adenylosuccinate synthase (PurA) | >20 | 7.9 ± 3.7 |
| Inosine monophosphate dehydrogenase (GuaB) | 3.1 ± 0.1 | 8.9 ± 4.2 |
| Aspartate carbamoyltransferase (PyrB) | 2.9 ± 0.4 | 7.2 ± 3.3 |
| Bifunctional purine biosynthesis protein (PurH) | 4.0 ± 1.2 | 1.1 ± 0.3 |
| Posttranslational modification | ||
| Chaperonin GroEL 60-kDa protein (GroEL) | 1.0 ± 0.6 | 0.8 ± 0.1 |
| Heat shock 70-kDa protein (DnaK) | 0.4 ± 0.1 | 0.4 ± 0.1 |
| Carbohydrate transport and metabolism | ||
| Phosphoglycerate kinase (Pgk) | 7.5 ± 2.3 | 1.3 ± 0.4 |
| Pyruvate kinase (Pyk) | 7.9 ± 3.2 | 1.3 ± 0.5 |
| Phosphotransferase system, enzyme I (PtsI) | 1.1 ± 0.3 | 1.6 ± 0.7 |
| Glyceraldehyde 3-phosphate dehydrogenase (GapA) | 1.8 ± 0.7 | 1.7 ± 0.9 |
| Fructose-bisphosphate aldolase (FbaA) | 1.6 ± 0.5 | 0.6 ± 0.2 |
| Citrate lyase beta chain (CitE) | Not matched | 0.4 ± 0.1 |
| Enolase (EnoA) | 1.9 ± 0.6 | 0.9 ± 0.3 |
| Amino acid transport and metabolism | ||
| Peptidase T (PepT) | 5.4 ± 2.6 | 0.9 ± 0.3 |
| Serine hydroxymethyl-transferase (GlyA) | 5.0 ± 1.7 | 2.6 ± 0.6 |
| α-Acetolactate synthase (Als) | 1.4 ± 0.3 | 0.2 ± 0.1 |
| Translation | ||
| Elongation factor G (FusA) | >20 | 3.2 ± 0.9 |
| Elongation factor Tu (Tuf) | 5.3 ± 1.1 | 1.3 ± 0.3 |
| Methionyl-tRNA formyltransferase (Fmt) | 5.8 ± 3.6 | 0.5 ± 0.2 |
| 30S ribosomal protein S2 (RpsB) | 5.2 ± 1.3 | 1.1 ± 0.4 |
| Cell division | ||
| Cell division protein (FtsZ) | 4.5 ± 1.8 | 2.3 ± 0.3 |
| UDP-N-acetylmuramate-alanine synthase (MurC) | 1.8 ± 0.7 | 0.9 ± 0.4 |
| Energy production and conversion | ||
| Glycerol-3-phosphate dehydrogenase (GpdA) | 7.4 ± 3.8 | 3.5 ± 0.9 |
| PDH E1 component alpha subunit (PdhA) | 3.3 ± 1.2 | 0.8 ± 0.1 |
| Malolactic enzyme (MleS) | Not matched | 1.7 ± 0.8 |
| Transcription | ||
| Carbon catabolite control protein (CcpA) | 7.9 ± 3.3 | 2.4 ± 0.4 |
| Coenzyme transport and metabolism | ||
| NH3-dependent NAD+ synthase (NadE) | >20 | 0.7 ± 0.2 |
| DNA recombination | ||
| Recombinase A (RecA) | Not matched | 0.8 ± 0.3 |
a
Expression changes are presented as the averages of induction (fold in the lag phase to the stationary phase (Lag/Stat) ± standard deviation [SD]) obtained for four biological replicates. COG, cluster of orthologous groups.
b
Induction values of <0.5-fold and >2-fold are denoted in boldface type.