Dipeptidyl-Peptidases and Tripeptidyl-Peptidases: A subclass of exopeptidases that includes enzymes which cleave either two or three AMINO ACIDS from the end of a peptide chain.Peptidyl-Dipeptidase A: A peptidyl-dipeptidase that catalyzes the release of a C-terminal dipeptide, -Xaa-*-Xbb-Xcc, when neither Xaa nor Xbb is Pro. It is a Cl(-)-dependent, zinc glycoprotein that is generally membrane-bound and active at neutral pH. It may also have endopeptidase activity on some substrates. (From Enzyme Nomenclature, 1992) EC EXOPEPTIDASES that specifically act on dipeptides. EC 3.4.13.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.Dipeptides: Peptides composed of two amino acid units.Cilastatin: A renal dehydropeptidase-I and leukotriene D4 dipeptidase inhibitor. Since the antibiotic, IMIPENEM, is hydrolyzed by dehydropeptidase-I, which resides in the brush border of the renal tubule, cilastatin is administered with imipenem to increase its effectiveness. The drug also inhibits the metabolism of leukotriene D4 to leukotriene E4.Sparsomycin: An antitumor antibiotic produced by Streptomyces sparsogenes. It inhibits protein synthesis in 70S and 80S ribosomal systems.Glutamate Carboxypeptidase II: A metallocarboxypeptidase that is predominantly expressed as a membrane-bound enzyme. It catalyzes the hydrolysis of an unsubstituted, C-terminal glutamyl residue, typically from PTEROYLPOLYGLUTAMIC ACIDS. It was formerly classified as EC 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.Aminopeptidases: A subclass of EXOPEPTIDASES that act on the free N terminus end of a polypeptide liberating a single amino acid residue. EC 3.4.11.Ribosomes: Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.Phosphatidylinositol Diacylglycerol-Lyase: A phosphorus-oxygen lyase found primarily in BACTERIA. The enzyme catalyzes the cleavage of a phosphoester linkage in 1-phosphatidyl-1D-myo-inositol to form 1D-myo-inositol 1,2-cyclic phosphate and diacylglycerol. The enzyme was formerly classified as a phosphoric diester hydrolase (EC and is often referred to as a TYPE C PHOSPHOLIPASES. However it is now known that a cyclic phosphate is the final product of this enzyme and that water does not enter into the reaction.Phosphoinositide Phospholipase C: A type C phospholipase with specificity towards PHOSPHATIDYLINOSITOLS that contain INOSITOL 1,4,5-TRISPHOSPHATE. Many of the enzymes listed under this classification are involved in intracellular signaling.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Peptidylprolyl Isomerase: An enzyme that catalyzes the isomerization of proline residues within proteins. EC Compounds containing carbohydrate or glycosyl groups linked to phosphatidylinositols. They anchor GPI-LINKED PROTEINS or polysaccharides to cell membranes.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.Hydrolysis: The process of cleaving a chemical compound by the addition of a molecule of water.Alanine Dehydrogenase: An NAD-dependent enzyme that catalyzes the reversible DEAMINATION of L-ALANINE to PYRUVATE and AMMONIA. The enzyme is needed for growth when ALANINE is the sole CARBON or NITROGEN source. It may also play a role in CELL WALL synthesis because L-ALANINE is an important constituent of the PEPTIDOGLYCAN layer.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.Leukotriene E4: A biologically active principle of SRS-A that is formed from LEUKOTRIENE D4 via a peptidase reaction that removes the glycine residue. The biological actions of LTE4 are similar to LTC4 and LTD4. (From Dictionary of Prostaglandins and Related Compounds, 1990)Puromycin: A cinnamamido ADENOSINE found in STREPTOMYCES alboniger. It inhibits protein synthesis by binding to RNA. It is an antineoplastic and antitrypanosomal agent and is used in research as an inhibitor of protein synthesis.RNA, Ribosomal, 23S: Constituent of 50S subunit of prokaryotic ribosomes containing about 3200 nucleotides. 23S rRNA is involved in the initiation of polypeptide synthesis.Dipeptidyl Peptidase 4: A serine protease that catalyses the release of an N-terminal dipeptide. Several biologically-active peptides have been identified as dipeptidyl peptidase 4 substrates including INCRETINS; NEUROPEPTIDES; and CHEMOKINES. The protein is also found bound to ADENOSINE DEAMINASE on the T-CELL surface and is believed to play a role in T-cell activation.Kinetics: The rate dynamics in chemical or physical systems.Haloarcula marismortui: A species of halophilic archaea distinguished by its production of acid from sugar. This species was previously called Halobacterium marismortui.SRS-A: A group of LEUKOTRIENES; (LTC4; LTD4; and LTE4) that is the major mediator of BRONCHOCONSTRICTION; HYPERSENSITIVITY; and other allergic reactions. Earlier studies described a "slow-reacting substance of ANAPHYLAXIS" released from lung by cobra venom or after anaphylactic shock. The relationship between SRS-A leukotrienes was established by UV which showed the presence of the conjugated triene. (From Merck Index, 11th ed)Microvilli: Minute projections of cell membranes which greatly increase the surface area of the cell.Swine: Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).Vibrio alginolyticus: A species of gram-negative, halophilic bacteria, in the genus VIBRIO. It is considered part of normal marine flora and commonly associated with ear infections and superficial wounds exposed to contaminated water sources.DiazomethaneEscherichia 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.Kidney Cortex: The outer zone of the KIDNEY, beneath the capsule, consisting of KIDNEY GLOMERULUS; KIDNEY TUBULES, DISTAL; and KIDNEY TUBULES, PROXIMAL.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Oligopeptides: Peptides composed of between two and twelve amino acids.Protease Inhibitors: Compounds which inhibit or antagonize biosynthesis or actions of proteases (ENDOPEPTIDASES).RNA, Transfer, Amino Acyl: Intermediates in protein biosynthesis. The compounds are formed from amino acids, ATP and transfer RNA, a reaction catalyzed by aminoacyl tRNA synthetase. They are key compounds in the genetic translation process.RNA, Transfer: The small RNA molecules, 73-80 nucleotides long, that function during translation (TRANSLATION, GENETIC) to align AMINO ACIDS at the RIBOSOMES in a sequence determined by the mRNA (RNA, MESSENGER). There are about 30 different transfer RNAs. Each recognizes a specific CODON set on the mRNA through its own ANTICODON and as aminoacyl tRNAs (RNA, TRANSFER, AMINO ACYL), each carries a specific amino acid to the ribosome to add to the elongating peptide chains.Carboxypeptidases: Enzymes that act at a free C-terminus of a polypeptide to liberate a single amino acid residue.Phosphoric Diester Hydrolases: A class of enzymes that catalyze the hydrolysis of one of the two ester bonds in a phosphodiester compound. EC 3.1.4.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Trehalase: An enzyme that catalyzes the conversion of alpha,alpha-trehalose and water to D-glucose. EC Hydrolase: Catalyzes the hydrolysis of pteroylpolyglutamic acids in gamma linkage to pterolylmonoglutamic acid and free glutamic acid. EC A subclass of PEPTIDE HYDROLASES that catalyze the internal cleavage of PEPTIDES or PROTEINS.gamma-Glutamyltransferase: An enzyme, sometimes called GGT, with a key role in the synthesis and degradation of GLUTATHIONE; (GSH, a tripeptide that protects cells from many toxins). It catalyzes the transfer of the gamma-glutamyl moiety to an acceptor amino acid.Lincomycin: An antibiotic produced by Streptomyces lincolnensis var. lincolnensis. It has been used in the treatment of staphylococcal, streptococcal, and Bacteroides fragilis infections.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.PhenanthrolinesSequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Molecular Weight: The sum of the weight of all the atoms in a molecule.Ribosomal Proteins: Proteins found in ribosomes. They are believed to have a catalytic function in reconstituting biologically active ribosomal subunits.RNA, Transfer, Pro: A transfer RNA which is specific for carrying proline to sites on the ribosomes in preparation for protein synthesis.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Stereoisomerism: The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Peptide Chain Elongation, Translational: A process of GENETIC TRANSLATION, when an amino acid is transferred from its cognate TRANSFER RNA to the lengthening chain of PEPTIDES.Thienamycins: Beta-lactam antibiotics that differ from PENICILLINS in having the thiazolidine sulfur atom replaced by carbon, the sulfur then becoming the first atom in the side chain. They are unstable chemically, but have a very broad antibacterial spectrum. Thienamycin and its more stable derivatives are proposed for use in combinations with enzyme inhibitors.Bacterial Proteins: Proteins found in any species of bacterium.Electrophoresis, Disc: Electrophoresis in which discontinuities in both the voltage and pH gradients are introduced by using buffers of different composition and pH in the different parts of the gel column. The term 'disc' was originally used as an abbreviation for 'discontinuous' referring to the buffers employed, and does not have anything to do with the shape of the separated zones.Peptides: Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.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.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Ribosome Subunits, Large, Bacterial: The large subunit of the eubacterial 70s ribosome. It is composed of the 23S RIBOSOMAL RNA, the 5S RIBOSOMAL RNA, and about 37 different RIBOSOMAL PROTEINS.Pyrimidine Nucleosides: Pyrimidines with a RIBOSE attached that can be phosphorylated to PYRIMIDINE NUCLEOTIDES.RNA, Ribosomal: The most abundant form of RNA. Together with proteins, it forms the ribosomes, playing a structural role and also a role in ribosomal binding of mRNA and tRNAs. Individual chains are conventionally designated by their sedimentation coefficients. In eukaryotes, four large chains exist, synthesized in the nucleolus and constituting about 50% of the ribosome. (Dorland, 28th ed)Acyltransferases: Enzymes from the transferase class that catalyze the transfer of acyl groups from donor to acceptor, forming either esters or amides. (From Enzyme Nomenclature 1992) EC 2.3.Structure-Activity Relationship: The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.Detergents: Purifying or cleansing agents, usually salts of long-chain aliphatic bases or acids, that exert cleansing (oil-dissolving) and antimicrobial effects through a surface action that depends on possessing both hydrophilic and hydrophobic properties.Leucine: An essential branched-chain amino acid important for hemoglobin formation.Glycolipids: Any compound containing one or more monosaccharide residues bound by a glycosidic linkage to a hydrophobic moiety such as an acylglycerol (see GLYCERIDES), a sphingoid, a ceramide (CERAMIDES) (N-acylsphingoid) or a prenyl phosphate. (From IUPAC's webpage)Chromatography, Gel: Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.Hydrolases: Any member of the class of enzymes that catalyze the cleavage of the substrate and the addition of water to the resulting molecules, e.g., ESTERASES, glycosidases (GLYCOSIDE HYDROLASES), lipases, NUCLEOTIDASES, peptidases (PEPTIDE HYDROLASES), and phosphatases (PHOSPHORIC MONOESTER HYDROLASES). EC 3.Amino Acid Isomerases: Enzymes that catalyze either the racemization or epimerization of chiral centers within amino acids or derivatives. EC 5.1.1.Lactobacillus: A genus of gram-positive, microaerophilic, rod-shaped bacteria occurring widely in nature. Its species are also part of the many normal flora of the mouth, intestinal tract, and vagina of many mammals, including humans. Pathogenicity from this genus is rare.RNA, Bacterial: Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.Dihydrolipoamide Dehydrogenase: A flavoprotein containing oxidoreductase that catalyzes the reduction of lipoamide by NADH to yield dihydrolipoamide and NAD+. The enzyme is a component of several MULTIENZYME COMPLEXES.GPI-Linked Proteins: A subclass of lipid-linked proteins that contain a GLYCOSYLPHOSPHATIDYLINOSITOL LINKAGE which holds them to the CELL MEMBRANE.Peptide Chain Termination, Translational: A process of GENETIC TRANSLATION whereby the terminal amino acid is added to a lengthening polypeptide. This termination process is signaled from the MESSENGER RNA, by one of three termination codons (CODON, TERMINATOR) that immediately follows the last amino acid-specifying CODON.RNA, Transfer, Phe: A transfer RNA which is specific for carrying phenylalanine to sites on the ribosomes in preparation for protein synthesis.Metals: Electropositive chemical elements characterized by ductility, malleability, luster, and conductance of heat and electricity. They can replace the hydrogen of an acid and form bases with hydroxyl radicals. (Grant & Hackh's Chemical Dictionary, 5th ed)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.