Differential transcription of the genes for PTS EII and ABC transporters following growth of S. mutans UA159 in glucose and fructose. Microarray results are presented as vertical bars. The numerical ORF designations for genes encoding sugar transporters are presented on the x axis. A full list of the gene product names is presented in Fig. 1. The value of the normalized expression signal is presented on the y axis. Transcription of the gene gyrA (SMU.1114) served as an endogenous control because it did not show significant variation of transcription under the conditions compared. A total of 10 glucose- and 10 fructose-grown samples were analyzed in five independent experiments. Two biological replicates were grown and tested in each experiment for each sugar, and thus we present the average results for two samples grown under the same condition: A, glucose; B, fructose.

Comparison of microarray and RT-PCR results for selected sugar transporter genes. Vertical bars represent the FC of gene transcription for an experimental condition versus baseline. In most cases the baseline was a glucose-grown sample, except for samples grown in cellobiose and mannose, which were also compared to mannitol. For both sets of results, the FCs are presented in log₂ scale (y axis). Results presented above the x axis represent an increase in transcription, and results below the x axis represent a decrease in transcription. The numerical ORF designations for the sugar transporter genes are presented on the x axis. A full list of gene product names is presented in Fig. 1. Experimental conditions (left to right) compared to glucose-grown samples: SMU.1596, cellobiose; SMU.1958 and SMU.1877, mannose; SMU.1185 and SMU.312, mannitol; SMU.878 and SMU.2038, raffinose; SMU.2047, SMU.1568, and SMU.1569, maltose; SMU.1958, SMU.872, SMU.2047, SMU.1841, and SMU.1877, fructose; SMU.2047, SMU.1568, and SMU.1569, maltotriose; SMU.1841, SMU.1568, SMU.1569, SMU.1958, SMU.878, SMU.1877, SMU.2047, and SMU.872, sucrose. Experimental conditions compared to mannitol-grown samples: SMU.1596, cellobiose; SMU.1958, mannose.

Schematic presentation of the genetic loci involved in transport and catabolism of the sugars analyzed in this study. Arrows represent the genes. The probable function of each gene is listed below. The numbers represent numeric designation of the ORFs listed in the S. mutans UA159 sequencing database (NCBI) (4). The ORFs are listed in 5′-to-3′ order. Descriptions of the gene products are redefined compared to the original annotation (4) as a result of this transcriptional study. The probable functions of the genes are as follows: SMU.2047, PTS system, glucose/maltose-specific IIABC; SMU.1841, PTS system, sucrose-specific IIABC; SMU.1843, sucrose-6-phosphate hydrolase; SMU.1844, sucrose operon repressor; SMU.1185, PTS system, mannitol-specific EIIBC; SMU.1184, transcriptional regulator, antiterminator; SMU.1183, PTS system, mannitol-specific EIIA; SMU.1182, mannitol-1-phosphate dehydrogenase; SMU.1498, lactose operon repressor; SMU.1496, galactose-6-phosphate isomerase, subunit LacA; SMU.1495, galactose-6-phosphate isomerase, subunit LacB; SMU.1494, tagatose-6-phosphate kinase; SMU.1493, tagatose-1,6-bisphosphate aldolase; SMU.1492, PTS system, lactose-specific EIIA (permease EIIA-LAC); SMU.1491, PTS system, lactose-specific EIIBC (permease EIIBC-LAC); SMU.1490, 6-phospho-beta-galactosidase; SMU.1489, part of lactose regulon, LacX; SMU.1488, part of lactose regulon; SMU.308, sorbitol and mannitol-6-phosphate dehydrogenase; SMU.309, regulator of sorbitol and mannitol operon; SMU.310, sorbitol and mannitol operon activator; SMU.311, PTS system, sorbitol- and mannitol-specific EIIC2; SMU.312; PTS system, sorbitol- and mannitol-specific EIIBC; SMU.313, PTS system, sorbitol- and mannitol-specific EIIA; SMU.314, part of sorbitol and mannitol regulon; SMU.870, transcriptional regulator of fructose operon; SMU.871, fructose-phosphate kinase; SMU.872, PTS system, fructose-specific EIIABC; SMU.1601, phospho-beta-glucosidase; SMU.1600, PTS system, cellobiose-specific EIIB; SMU.1599, transcriptional regulator of cellobiose operon, possible antiterminator; SMU.1598, PTS system, cellobiose-specific EIIA; SMU.1597, part of cellobiose operon; SMU.1596, PTS system, cellobiose-specific EIIC; SMU.1877, PTS system, mannose/glucose-specific EIIAB; SMU.1878, PTS system, mannose/glucose-specific EIIC; SMU.1879, PTS system, mannose/glucose-specific EIID; SMU.1961, PTS system, mannose/fructose-specific EIIA; SMU.1960, PTS system, mannose/fructose-specific EIIB; SMU.1958, PTS system, mannose/fructose-specific EIIC; SMU.1957, PTS system, mannose/fructose-specific EIID; SMU.1956, part of the mannose/fructose-specific PTS; SMU.2040, transcriptional regulator, repressor of the trehalose operon; SMU.2038, PTS system, trehalose-specific EIIABC; SMU.2037, trehalose-6-phosphate hydrolase TreA; SMU.1566, maltodextrin and maltose operon transcriptional repressor; SMU.1568, maltodextrin and maltose ABC transporter, sugar-binding protein MalX; SMU.1569, maltodextrin and maltose ABC transporter, MalG permease; SMU.1570, maltodextrin and maltose ABC transporter, permease; SMU.1571, ABC transporter, ATP-binding protein; SMU.876, MSM operon regulatory protein; SMU.877, MSM operon, alpha-galactosidase; SMU.878, MSM ABC transporter, sugar-binding protein precursor MsmE; SMU.879, MSM ABC transporter, permease protein MsmF; SMU.880, MSM ABC transporter, permease protein MsmG; SMU.881, MSM operon, sucrose phosphorylase, GtfA; SMU.882, MSM operon, ABC transporter, ATP-binding protein MsmK; SMU.883, MSM operon, dextran glucosidase DexB.

Differential transcription of genes for PTS EII and ABC transporters following growth of S. mutans UA159 in different sugars. Microarray results are presented as vertical bars. The numerical ORF designations for genes encoding sugar transporters are presented on the x axis. A full list of the gene product names is presented in Fig. 1. The value of the normalized expression signal is presented on the y axis. Two biological replicates were analyzed for each sugar, and thus we present the average results for samples grown under each condition. A, fructose, mannose, sucrose with dextranase, and glucose with dextranase; B, lactose, galactose, raffinose, and stachyose; C, trehalose, maltose, maltotriose, cellobiose, and mannitol.