PeptidoglycanMuramic Acids: Compounds consisting of glucosamine and lactate joined by an ether linkage. They occur naturally as N-acetyl derivatives in peptidoglycan, the characteristic polysaccharide composing bacterial cell walls. (From Dorland, 28th ed)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.Diaminopimelic AcidPeptidoglycan Glycosyltransferase: A hexosyltransferase involved in the transfer of disaccharide molecules to the peptidoglycan structure of the CELL WALL SKELETON. It plays an important role in the genesis of the bacterial CELL WALL.N-Acetylmuramoyl-L-alanine Amidase: An autolytic enzyme bound to the surface of bacterial cell walls. It catalyzes the hydrolysis of the link between N-acetylmuramoyl residues and L-amino acid residues in certain cell wall glycopeptides, particularly peptidoglycan. EC 3.5.1.28.Uridine Diphosphate N-Acetylmuramic Acid: A nucleoside diphosphate sugar which is formed from UDP-N-acetylglucosamine and phosphoenolpyruvate. It serves as the building block upon which peptidoglycan is formed.Muramidase: A basic enzyme that is present in saliva, tears, egg white, and many animal fluids. It functions as an antibacterial agent. The enzyme catalyzes the hydrolysis of 1,4-beta-linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in peptidoglycan and between N-acetyl-D-glucosamine residues in chitodextrin. EC 3.2.1.17.Bacteriolysis: Rupture of bacterial cells due to mechanical force, chemical action, or the lytic growth of BACTERIOPHAGES.Penicillin-Binding Proteins: Bacterial proteins that share the property of binding irreversibly to PENICILLINS and other ANTIBACTERIAL AGENTS derived from LACTAMS. The penicillin-binding proteins are primarily enzymes involved in CELL WALL biosynthesis including MURAMOYLPENTAPEPTIDE CARBOXYPEPTIDASE; PEPTIDE SYNTHASES; TRANSPEPTIDASES; and HEXOSYLTRANSFERASES.Bacterial Proteins: Proteins found in any species of bacterium.Peptidyl Transferases: Acyltransferases that use AMINO ACYL TRNA as the amino acid donor in formation of a peptide bond. There are ribosomal and non-ribosomal peptidyltransferases.Teichoic Acids: Bacterial polysaccharides that are rich in phosphodiester linkages. They are the major components of the cell walls and membranes of many bacteria.Actinomycetales: An order of gram-positive, primarily aerobic BACTERIA that tend to form branching filaments.Muramoylpentapeptide Carboxypeptidase: Enzyme which catalyzes the peptide cross-linking of nascent CELL WALL; PEPTIDOGLYCAN.Micrococcus: A genus of gram-positive, spherical bacteria found in soils and fresh water, and frequently on the skin of man and other animals.Pimelic Acids: A group of compounds that are derivatives of heptanedioic acid with the general formula R-C7H11O4.Acetylmuramyl-Alanyl-Isoglutamine: Peptidoglycan immunoadjuvant originally isolated from bacterial cell wall fragments; also acts as pyrogen and may cause arthritis; stimulates both humoral and cellular immunity.Staphylococcus aureus: Potentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications.Penicillin G: A penicillin derivative commonly used in the form of its sodium or potassium salts in the treatment of a variety of infections. It is effective against most gram-positive bacteria and against gram-negative cocci. It has also been used as an experimental convulsant because of its actions on GAMMA-AMINOBUTYRIC ACID mediated synaptic transmission.Hexosyltransferases: Enzymes that catalyze the transfer of hexose groups. EC 2.4.1.-.Streptococcaceae: A family of gram-positive non-sporing bacteria including many parasitic, pathogenic, and saprophytic forms.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.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.Lysostaphin: A 25-kDa peptidase produced by Staphylococcus simulans which cleaves a glycine-glcyine bond unique to an inter-peptide cross-bridge of the STAPHYLOCOCCUS AUREUS cell wall. EC 3.4.24.75.RNA, Ribosomal, 16S: Constituent of 30S subunit prokaryotic ribosomes containing 1600 nucleotides and 21 proteins. 16S rRNA is involved in initiation of polypeptide synthesis.Cycloserine: Antibiotic substance produced by Streptomyces garyphalus.Amino Sugars: SUGARS containing an amino group. GLYCOSYLATION of other compounds with these amino sugars results in AMINOGLYCOSIDES.DNA, Ribosomal: DNA sequences encoding RIBOSOMAL RNA and the segments of DNA separating the individual ribosomal RNA genes, referred to as RIBOSOMAL SPACER DNA.Bacillus subtilis: A species of gram-positive bacteria that is a common soil and water saprophyte.Acetylglucosamine: The N-acetyl derivative of glucosamine.Base Composition: The relative amounts of the PURINES and PYRIMIDINES in a nucleic acid.Serine-Type D-Ala-D-Ala Carboxypeptidase: A carboxypeptidase that is specific for proteins that contain two ALANINE residues on their C-terminal. Enzymes in this class play an important role in bacterial CELL WALL biosynthesis.Alanine: A non-essential amino acid that occurs in high levels in its free state in plasma. It is produced from pyruvate by transamination. It is involved in sugar and acid metabolism, increases IMMUNITY, and provides energy for muscle tissue, BRAIN, and the CENTRAL NERVOUS SYSTEM.DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.Carboxypeptidases: Enzymes that act at a free C-terminus of a polypeptide to liberate a single amino acid residue.Selenomonas: Curved bacteria, usually crescent-shaped rods, with ends often tapered, occurring singly, in pairs, or short chains. They are non-encapsulated, non-sporing, motile, and ferment glucose. Selenomonas are found mainly in the human buccal cavity, the rumen of herbivores, and the cecum of pigs and several rodents. (From Bergey's Manual of Determinative Bacteriology, 9th ed)Vancomycin: Antibacterial obtained from Streptomyces orientalis. It is a glycopeptide related to RISTOCETIN that inhibits bacterial cell wall assembly and is toxic to kidneys and the inner ear.Nod1 Signaling Adaptor Protein: A NOD-signaling adaptor protein that contains a C-terminal leucine-rich domain which recognizes bacterial PEPTIDOGLYCAN. It signals via an N-terminal caspase recruitment domain that interacts with other CARD SIGNALING ADAPTOR PROTEINS such as RIP SERINE-THEONINE KINASES. It plays a role in the host defense response by signaling the activation of CASPASES and the MAP KINASE SIGNALING SYSTEM.GlucosamineVitamin 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.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Spores, Bacterial: Heat and stain resistant, metabolically inactive bodies formed within the vegetative cells of bacteria of the genera Bacillus and Clostridium.AmidohydrolasesCadaverine: A foul-smelling diamine formed by bacterial decarboxylation of lysine.Bacillus megaterium: A species of bacteria whose spores vary from round to elongate. It is a common soil saprophyte.Penicillins: A group of antibiotics that contain 6-aminopenicillanic acid with a side chain attached to the 6-amino group. The penicillin nucleus is the chief structural requirement for biological activity. The side-chain structure determines many of the antibacterial and pharmacological characteristics. (Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed, p1065)Peptide Synthases: Ligases that catalyze the joining of adjacent AMINO ACIDS by the formation of carbon-nitrogen bonds between their carboxylic acid groups and amine groups.Bacillus: A genus of BACILLACEAE that are spore-forming, rod-shaped cells. Most species are saprophytic soil forms with only a few species being pathogenic.Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.Anti-Bacterial Agents: Substances that reduce the growth or reproduction of BACTERIA.Bacillaceae: A family of bacteria which produce endospores. They are mostly saprophytes from soil, but a few are insect or animal parasites or pathogens.Gram-Positive Bacteria: Bacteria which retain the crystal violet stain when treated by Gram's method.Uridine Diphosphate N-Acetylglucosamine: Serves as the biological precursor of insect chitin, of muramic acid in bacterial cell walls, and of sialic acids in mammalian glycoproteins.Amdinocillin: An amidinopenicillanic acid derivative with broad spectrum antibacterial action.Toll-Like Receptor 2: A pattern recognition receptor that forms heterodimers with other TOLL-LIKE RECEPTORS. It interacts with multiple ligands including PEPTIDOGLYCAN, bacterial LIPOPROTEINS, lipoarabinomannan, and a variety of PORINS.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.Micrococcaceae: A family of bacteria ranging from free living and saprophytic to parasitic and pathogenic forms.Glycopeptides: Proteins which contain carbohydrate groups attached covalently to the polypeptide chain. The protein moiety is the predominant group with the carbohydrate making up only a small percentage of the total weight.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)Soil Microbiology: The presence of bacteria, viruses, and fungi in the soil. This term is not restricted to pathogenic organisms.Bacitracin: A complex of cyclic peptide antibiotics produced by the Tracy-I strain of Bacillus subtilis. The commercial preparation is a mixture of at least nine bacitracins with bacitracin A as the major constituent. It is used topically to treat open infections such as infected eczema and infected dermal ulcers. (From Goodman and Gilman, The Pharmacological Basis of Therapeutics, 8th ed, p1140)Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Autolysis: The spontaneous disintegration of tissues or cells by the action of their own autogenous enzymes.Chromatography, Paper: An analytical technique for resolution of a chemical mixture into its component compounds. Compounds are separated on an adsorbent paper (stationary phase) by their varied degree of solubility/mobility in the eluting solvent (mobile phase).Aminoacyltransferases: Enzymes that catalyze the transfer of an aminoacyl group from donor to acceptor resulting in the formation of an ester or amide linkage. EC 2.3.2.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.Neisseria gonorrhoeae: A species of gram-negative, aerobic bacteria primarily found in purulent venereal discharges. It is the causative agent of GONORRHEA.Nod2 Signaling Adaptor Protein: A NOD signaling adaptor protein that contains two C-terminal leucine-rich domains which recognize bacterial PEPTIDOGLYCAN. It signals via an N-terminal capase recruitment domain that interacts with other CARD SIGNALING ADAPTOR PROTEINS such as RIP SERINE-THEONINE KINASES. The protein plays a role in the host defense response by signaling the activation of CASPASES and the MAP KINASE SIGNALING SYSTEM. Mutations of the gene encoding the nucleotide oligomerization domain 2 protein have been associated with increased susceptibility to CROHN DISEASE.Amino Acids: Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.Enterococcus faecalis: A species of gram-positive, coccoid bacteria commonly isolated from clinical specimens and the human intestinal tract. Most strains are nonhemolytic.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Chromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.Galactans: Polysaccharides composed of repeating galactose units. They can consist of branched or unbranched chains in any linkages.Alanine Racemase: A pyridoxal-phosphate protein that reversibly catalyzes the conversion of L-alanine to D-alanine. EC 5.1.1.1.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Gene Expression Regulation, Bacterial: Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.Polysaccharides, Bacterial: Polysaccharides found in bacteria and in capsules thereof.Bdellovibrio: A genus of bacteria capable of developing within other bacteria.Glycosyltransferases: Enzymes that catalyze the transfer of glycosyl groups to an acceptor. Most often another carbohydrate molecule acts as an acceptor, but inorganic phosphate can also act as an acceptor, such as in the case of PHOSPHORYLASES. Some of the enzymes in this group also catalyze hydrolysis, which can be regarded as transfer of a glycosyl group from the donor to water. Subclasses include the HEXOSYLTRANSFERASES; PENTOSYLTRANSFERASES; SIALYLTRANSFERASES; and those transferring other glycosyl groups. EC 2.4.Lactams: Cyclic AMIDES formed from aminocarboxylic acids by the elimination of water. Lactims are the enol forms of lactams.Bacteria: One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.Species Specificity: The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.Endopeptidases: A subclass of PEPTIDE HYDROLASES that catalyze the internal cleavage of PEPTIDES or PROTEINS.Bambermycins: Antibiotic complex obtained from Streptomyces bambergiensis containing mainly Moenomycins A and C. They are used as feed additives and growth promoters for poultry, swine, and cattle.Hydrolysis: The process of cleaving a chemical compound by the addition of a molecule of water.Uridine Diphosphate SugarsCell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Mycobacterium smegmatis: A rapid-growing, nonphotochromogenic species of MYCOBACTERIUM originally isolated from human smegma and found also in soil and water. (From Dorland, 28th ed)RNA, Bacterial: Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.Lipopolysaccharides: Lipid-containing polysaccharides which are endotoxins and important group-specific antigens. They are often derived from the cell wall of gram-negative bacteria and induce immunoglobulin secretion. The lipopolysaccharide molecule consists of three parts: LIPID A, core polysaccharide, and O-specific chains (O ANTIGENS). When derived from Escherichia coli, lipopolysaccharides serve as polyclonal B-cell mitogens commonly used in laboratory immunology. (From Dorland, 28th ed)Toll-Like Receptors: A family of pattern recognition receptors characterized by an extracellular leucine-rich domain and a cytoplasmic domain that share homology with the INTERLEUKIN 1 RECEPTOR and the DROSOPHILA toll protein. Following pathogen recognition, toll-like receptors recruit and activate a variety of SIGNAL TRANSDUCING ADAPTOR PROTEINS.Acetylglucosaminidase: A beta-N-Acetylhexosaminidase that catalyzes the hydrolysis of terminal, non-reducing 2-acetamido-2-deoxy-beta-glucose residues in chitobiose and higher analogs as well as in glycoproteins. Has been used widely in structural studies on bacterial cell walls and in the study of diseases such as MUCOLIPIDOSIS and various inflammatory disorders of muscle and connective tissue.Sodium Chloride: A ubiquitous sodium salt that is commonly used to season food.HexosaminesProtoplasts: The protoplasm and plasma membrane of plant, fungal, bacterial or archaeon cells without the CELL WALL.Bacillus cereus: A species of rod-shaped bacteria that is a common soil saprophyte. Its spores are widespread and multiplication has been observed chiefly in foods. Contamination may lead to food poisoning.Diamines: Organic chemicals which have two amino groups in an aliphatic chain.Staphylococcus: A genus of gram-positive, facultatively anaerobic, coccoid bacteria. Its organisms occur singly, in pairs, and in tetrads and characteristically divide in more than one plane to form irregular clusters. Natural populations of Staphylococcus are found on the skin and mucous membranes of warm-blooded animals. Some species are opportunistic pathogens of humans and animals.Propionibacteriaceae: A family of gram-positive bacteria found in dairy products or in the intestinal tracts of animals.Genes, Bacterial: The functional hereditary units of BACTERIA.Micrococcus luteus: A species of gram-positive, spherical bacteria whose organisms occur in tetrads and in irregular clusters of tetrads. The primary habitat is mammalian skin.