Article Figures & Data
Figures
- FIG. 1.
Schematic diagram outlining the procedure (SCOTS) used to obtain cDNAs for L. monocytogenes RNAs expressed in response to growth at a low temperature. (A) Process used to reduce rDNA sequence content and increase the representation of less abundant RNAs (normalized). (B) Differential hybridization method used for selective amplification of bacterial RNAs expressed in response to a reduced temperature. S:B, streptavidin:biotin.
- FIG. 2.
Northern hybridization analyses of RNAs from mid-log-phase L. monocytogenes 10403S cultures grown at 37 and 10°C. EcoRI-digested inserts from plasmid cDNA clones obtained by SCOTS were used as templates to prepare radiolabeled probes. Hybridization was performed as described in Materials and Methods. Nylon filters were subsequently hybridized with a 16S rDNA probe and a housekeeping gene (dapE) probe as controls. Table 2 lists the corresponding genes for SCOTS cDNA clones.
- FIG. 3.
Northern hybridization analyses of L. monocytogenes RNAs. Total RNA was isolated from mid-log-phase L. monocytogenes 10403S grown at either 37 or 10°C. RNAs were electrophoresed as described in Materials and Methods and stained with ethidium bromide to ensure that equivalent amounts of total RNA were present in the lanes (bottom panel). EcoRI-digested inserts from plasmid cDNA clones obtained by SCOTS were used as templates to prepare radiolabeled probes (top panel). Table 2 lists the genes corresponding to SCOTS cDNA clones.
Tables
- TABLE 1.
Oligonucleotides used for this study
Oligonucleotide Sequence F1 CTGGCTCAGGACGAACGCTGG B1 GCTGGCTCCATAAAGGTGACC F2 TCGGTAGGGTCACCTTTATGG B2 CTCACACTCACTGCTTGGACG F3 AATGGAAATGTGCGTCCAAGC B3 ACTTTTCAAATTGCCCGGCAG K9 GACACTCTCGAGACATCACCGGTACCNNNNNN F9 GCCGGAGCTCTGCAGAATTCNNNNNN K-N6 GACACTCTCGAGACATCACCGGTACC F-N6 GCCGGAGCTCTGCAGAATTC DapE5′ GGTTTTGGCATTTTCAGGGC DapE3′ GATTCTGTGTCCACTCGGTTCG - TABLE 2.
L. monocytogenes cDNA clones identified by SCOTS
Category SCOTS clone(s) Gene Predicted gene product GenBank accession no. Strain EGD-e Gene Chromosomal location (kb) Previously described L. monocytogenes cold-adaptive responses 12 flaA Flagellin X65624 lmo0690 724.9 25 flp Ferritin-like protein AJ244014 lmo0943 979.1 Regulatory adaptive responses 19, 62 rpoN (sigL) RNA polymerase sigma factor σ54 X93169.1 lmo2461 2535.2 73 lhkA Histidine kinase sensor AJ010495 lmo1508 1538.5 6 yycJ Two-component signal transduction system BAA11296 lmo0291 316.9 22 bglG Similar to transcription antiterminator BglG family lmo0501 536.3 75 adaB Similar to methyltransferase X53399 lmo0571 608.5 General microbial stress responses 70 groEL Major heat shock protein AF335323 lmo2068 2149.3 55 clpP Serine protease AF102775 lmo2612 2627.7 7 trxB Thioredoxin reductase AF009622 lmo2478 2554.4 60 clpB ClpB protease lmo2206 2297.2 Alterations in amino acid metabolism 17, 24, 45 hisJ Histidinol phosphate phosphatase D70002 lmo0570 607.4 18 trpG Anthranilate synthase S74362 lmo2749 2824.1 32 cysS Cysteinyl-tRNA synthetase L14580 lmo0239 259.5 65 aroA 3-Deoxy-d-arabino-heptulosonate 7-phosphate synthase X69545 lmo1600 1645.2 51 celD Endoglucanase D U07818 lmo1719 178.1 Alterations in degradative metabolism 15, 27, 39, 43, 64, 84 eutB Ethanolamine ammonia lyase heavy chain P19635 lmo1175 1203.6 79 mleA Similar to malolactic enzyme X82326 lmo1915 1988.2 Alterations of the L. monocytogenes cell surface 3 psr PBP5 synthesis repressor U42211 lmo0443 472.8 56 fbp Fibronectin-binding protein AJ132543 lmo0721 751.3 Proteins with unknown functions 4 Unknown conserved hypothetical protein lmo0599 lmo0599 640.3 26 Unknown protein lmo0170 lmo0170 168.0 50 Unknown protein lmo0719 lmo0719 750.0 69 Unknown protein lmo1535 lmo1535 1570.9
