ArabinoseAraC Transcription Factor: A transcription factor found in BACTERIA that positively and negatively regulates the expression of proteins required for the uptake and catabolism of L-ARABINOSE.XyloseMonosaccharides: Simple sugars, carbohydrates which cannot be decomposed by hydrolysis. They are colorless crystalline substances with a sweet taste and have the same general formula CnH2nOn. (From Dorland, 28th ed)Pentoses: A class of carbohydrates that contains five carbon atoms.Xylans: Polysaccharides consisting of xylose units.Galactans: Polysaccharides composed of repeating galactose units. They can consist of branched or unbranched chains in any linkages.Actinomycetales: An order of gram-positive, primarily aerobic BACTERIA that tend to form branching filaments.Genes, araC: Regulatory genes which encode a cyclic AMP receptor protein required for L-arabinose utilization in E. coli. It is an example of positive control or regulation of gene expression in the bacterial operon.PolysaccharidesCarbohydrates: The largest class of organic compounds, including STARCH; GLYCOGEN; CELLULOSE; POLYSACCHARIDES; and simple MONOSACCHARIDES. Carbohydrates are composed of carbon, hydrogen, and oxygen in a ratio of Cn(H2O)n.Galactose: An aldohexose that occurs naturally in the D-form in lactose, cerebrosides, gangliosides, and mucoproteins. Deficiency of galactosyl-1-phosphate uridyltransferase (GALACTOSE-1-PHOSPHATE URIDYL-TRANSFERASE DEFICIENCY DISEASE) causes an error in galactose metabolism called GALACTOSEMIA, resulting in elevations of galactose in the blood.Glycoside HydrolasesCarbohydrate Metabolism: Cellular processes in biosynthesis (anabolism) and degradation (catabolism) of CARBOHYDRATES.RNA, Ribosomal, 16S: Constituent of 30S subunit prokaryotic ribosomes containing 1600 nucleotides and 21 proteins. 16S rRNA is involved in initiation of polypeptide synthesis.Cell Wall: The outermost layer of a cell in most PLANTS; BACTERIA; FUNGI; and ALGAE. The cell wall is usually a rigid structure that lies external to the CELL MEMBRANE, and provides a protective barrier against physical or chemical agents.Fermentation: Anaerobic degradation of GLUCOSE or other organic nutrients to gain energy in the form of ATP. End products vary depending on organisms, substrates, and enzymatic pathways. Common fermentation products include ETHANOL and LACTIC ACID.DNA, Ribosomal: DNA sequences encoding RIBOSOMAL RNA and the segments of DNA separating the individual ribosomal RNA genes, referred to as RIBOSOMAL SPACER DNA.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Base Composition: The relative amounts of the PURINES and PYRIMIDINES in a nucleic acid.Micromonosporaceae: A family of gram-positive, saprophytic bacteria occurring in soil and aquatic environments.DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Gene Expression Regulation, Bacterial: Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.Rhamnose: A methylpentose whose L- isomer is found naturally in many plant glycosides and some gram-negative bacterial lipopolysaccharides.Soil Microbiology: The presence of bacteria, viruses, and fungi in the soil. This term is not restricted to pathogenic organisms.Escherichia coli Proteins: Proteins obtained from ESCHERICHIA COLI.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Operon: In bacteria, a group of metabolically related genes, with a common promoter, whose transcription into a single polycistronic MESSENGER RNA is under the control of an OPERATOR REGION.Xylosidases: A group of enzymes that catalyze the hydrolysis of alpha- or beta-xylosidic linkages. EC catalyzes the endo-hydrolysis of 1,4-beta-D-xylosidic linkages; EC catalyzes the endo-hydrolysis of 1,3-beta-D-xylosidic linkages; EC catalyzes the exo-hydrolysis of 1,4-beta-D-linkages from the non-reducing termini of xylans; and EC catalyzes the exo-hydrolysis of 1,3-beta-D-linkages from the non-reducing termini of xylans. Other xylosidases have been identified that catalyze the hydrolysis of alpha-xylosidic bonds.Gordonia Bacterium: A genus of gram-positive BACTERIA in the family Gordoniaceae, isolated from soil and from sputa of patients with chest disorders. It is also used for biotransformation of natural products.Bacterial Typing Techniques: Procedures for identifying types and strains of bacteria. The most frequently employed typing systems are BACTERIOPHAGE TYPING and SEROTYPING as well as bacteriocin typing and biotyping.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.MethylgalactosidesLignin: The most abundant natural aromatic organic polymer found in all vascular plants. Lignin together with cellulose and hemicellulose are the major cell wall components of the fibers of all wood and grass species. Lignin is composed of coniferyl, p-coumaryl, and sinapyl alcohols in varying ratios in different plant species. (From Merck Index, 11th ed)Bacterial Proteins: Proteins found in any species of bacterium.Transcription Initiation, Genetic: The process that starts the transcription of an RNA molecule. It includes the assembly of the initiation complex and establishment of the start site.Medicago sativa: A plant species of the family FABACEAE widely cultivated for ANIMAL FEED.Aldose-Ketose Isomerases: Enzymes that catalyze the interconversion of aldose and ketose compounds.Diaminopimelic AcidRoot Nodules, Plant: Knobbed structures formed from and attached to plant roots, especially of LEGUMES, which result from symbiotic infection by nitrogen fixing bacteria such as RHIZOBIUM or FRANKIA. Root nodules are structures related to MYCORRHIZAE formed by symbiotic associations with fungi.Artificial Gene Fusion: The in vitro fusion of GENES by RECOMBINANT DNA techniques to analyze protein behavior or GENE EXPRESSION REGULATION, or to merge protein functions for specific medical or industrial uses.Endo-1,4-beta Xylanases: Enzymes which catalyze the endohydrolysis of 1,4-beta-D-xylosidic linkages in XYLANS.Clostridium acetobutylicum: A species of gram-positive bacteria in the family Clostridiaceae, used for the industrial production of SOLVENTS.Pectins: High molecular weight polysaccharides present in the cell walls of all plants. Pectins cement cell walls together. They are used as emulsifiers and stabilizers in the food industry. They have been tried for a variety of therapeutic uses including as antidiarrheals, where they are now generally considered ineffective, and in the treatment of hypercholesterolemia.Glucose: A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.Vitamin K 2: A group of substances similar to VITAMIN K 1 which contains a ring of 2-methyl-1,4-naphthoquinione and an isoprenoid side chain of varying number of isoprene units. In vitamin K 2, each isoprene unit contains a double bond. They are produced by bacteria including the normal intestinal flora.Ribose: A pentose active in biological systems usually in its D-form.Fatty Acids: Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)Uronic Acids: Acids derived from monosaccharides by the oxidation of the terminal (-CH2OH) group farthest removed from the carbonyl group to a (-COOH) group. (From Stedmans, 26th ed)Xylitol: A five-carbon sugar alcohol derived from XYLOSE by reduction of the carbonyl group. It is as sweet as sucrose and used as a noncariogenic sweetener.Genes, rRNA: Genes, found in both prokaryotes and eukaryotes, which are transcribed to produce the RNA which is incorporated into RIBOSOMES. Prokaryotic rRNA genes are usually found in OPERONS dispersed throughout the GENOME, whereas eukaryotic rRNA genes are clustered, multicistronic transcriptional units.Culture Media: Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.