A structural subclass of streptogramins. They are cyclic hexadepsipeptides with approximate molecular weight of 800 that contain a characteristic 3-hydroxy picolinoyl exocyclic component.
A structural subclass of streptogramins that includes molecules containing unsaturated macrocyclic lactones with approximate molecular weight of 500 KDa.
A specific streptogramin group A antibiotic produced by Streptomyces graminofaciens and other bacteria.
A specific streptogramin group B antibiotic produced by Streptomyces graminofaciens and other bacteria.
A class of natural cyclic peptide antibiotics produced by certain subspecies of STREPTOMYCES. They include two structurally unrelated components, STREPTOGRAMIN GROUP A and STREPTOGRAMIN GROUP B, which generally act synergistically to inhibit bacterial growth.
A cyclic polypeptide antibiotic complex from Streptomyces virginiae, S. loidensis, S. mitakaensis, S. pristina-spiralis, S. ostreogriseus, and others. It consists of 2 major components, VIRGINIAMYCIN FACTOR M1 and virginiamycin Factor S1. It is used to treat infections with gram-positive organisms and as a growth promoter in cattle, swine, and poultry.
A family of LINCOMYCIN-related glycosides that contain a pyrrolidine ring linked via an amide-bond to a pyranose moiety. Individual members of this family are defined by the arrangement of specific constituent groups on the lyncomycin molecule. Many lincosamides are ANTIBIOTICS produced by a variety STREPTOMYCES species.
A group of often glycosylated macrocyclic compounds formed by chain extension of multiple PROPIONATES cyclized into a large (typically 12, 14, or 16)-membered lactone. Macrolides belong to the POLYKETIDES class of natural products, and many members exhibit ANTIBIOTIC properties.
A bacteriostatic antibiotic macrolide produced by Streptomyces erythreus. Erythromycin A is considered its major active component. In sensitive organisms, it inhibits protein synthesis by binding to 50S ribosomal subunits. This binding process inhibits peptidyl transferase activity and interferes with translocation of amino acids during translation and assembly of proteins.
Substances that reduce the growth or reproduction of BACTERIA.
Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.
Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)
A genus of bacteria that form a nonfragmented aerial mycelium. Many species have been identified with some being pathogenic. This genus is responsible for producing a majority of the ANTI-BACTERIAL AGENTS of practical value.
The ability of microorganisms, especially bacteria, to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).
The ability of bacteria to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).
One of the Indian Ocean Islands off the southeast coast of Africa. Its capital is Antananarivo. It was formerly called the Malagasy Republic. Discovered by the Portuguese in 1500, its history has been tied predominantly to the French, becoming a French protectorate in 1882, a French colony in 1896, and a territory within the French union in 1946. The Malagasy Republic was established in the French Community in 1958 but it achieved independence in 1960. Its name was changed to Madagascar in 1975. (From Webster's New Geographical Dictionary, 1988, p714)
A republic in central Africa south of CHAD and SUDAN, north of DEMOCRATIC REPUBLIC OF THE CONGO, and east of CAMEROON. The capital is Bangui.
Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).
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.
A verocytotoxin-producing serogroup belonging to the O subfamily of Escherichia coli which has been shown to cause severe food-borne disease. A strain from this serogroup, serotype H7, which produces SHIGA TOXINS, has been linked to human disease outbreaks resulting from contamination of foods by E. coli O157 from bovine origin.
A family of secreted proteins found associated with the EXTRACELLULAR MATRIX and cell surface receptors. They are believed to play a role in modulating the effects of a variety of GROWTH FACTORS and PROTEASES at the cell membrane extracellular matrix. The CCN protein family is named after three protypical members; CYSTEINE-RICH PROTEIN 61; CONNECTIVE TISSUE GROWTH FACTOR; and NEPHROBLASTOMA OVEREXPRESSED PROTEIN.
An early non-mammalian embryo that follows the MORULA stage. A blastula resembles a hollow ball with the layer of cells surrounding a fluid-filled cavity (blastocele). The layer of cells is called BLASTODERM.
An enzyme that transfers methyl groups from O(6)-methylguanine, and other methylated moieties of DNA, to a cysteine residue in itself, thus repairing alkylated DNA in a single-step reaction. EC
Proteins, generally found in the CYTOPLASM, that specifically bind ANDROGENS and mediate their cellular actions. The complex of the androgen and receptor migrates to the CELL NUCLEUS where it induces transcription of specific segments of DNA.
Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.
A federal area located between Maryland and Virginia on the Potomac river; it is coextensive with Washington, D.C., which is the capital of the United States.
The ability of bacteria to resist or to become tolerant to several structurally and functionally distinct drugs simultaneously. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).
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.
The systematic study of the complete DNA sequences (GENOME) of organisms.
The degree of 3-dimensional shape similarity between proteins. It can be an indication of distant AMINO ACID SEQUENCE HOMOLOGY and used for rational DRUG DESIGN.
Databases containing information about PROTEINS such as AMINO ACID SEQUENCE; PROTEIN CONFORMATION; and other properties.
Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A species of gram-positive, coccoid bacteria isolated from skin lesions, blood, inflammatory exudates, and the upper respiratory tract of humans. It is a group A hemolytic Streptococcus that can cause SCARLET FEVER and RHEUMATIC FEVER.
The 2nd cranial nerve which conveys visual information from the RETINA to the brain. The nerve carries the axons of the RETINAL GANGLION CELLS which sort at the OPTIC CHIASM and continue via the OPTIC TRACTS to the brain. The largest projection is to the lateral geniculate nuclei; other targets include the SUPERIOR COLLICULI and the SUPRACHIASMATIC NUCLEI. Though known as the second cranial nerve, it is considered part of the CENTRAL NERVOUS SYSTEM.
A subspecialty of internal medicine concerned with the study of neoplasms.
New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.
Tumors or cancer of the UROGENITAL SYSTEM in either the male or the female.
Critical and exhaustive investigation or experimentation, having for its aim the discovery of new facts and their correct interpretation, the revision of accepted conclusions, theories, or laws in the light of newly discovered facts, or the practical application of such new or revised conclusions, theories, or laws. (Webster, 3d ed)
Infections with bacteria of the genus STREPTOCOCCUS.
Expendable and nonexpendable equipment, supplies, apparatus, and instruments that are used in diagnostic, surgical, therapeutic, scientific, and experimental procedures.
Acceleration produced by the mutual attraction of two masses, and of magnitude inversely proportional to the square of the distance between the two centers of mass. It is also the force imparted by the earth, moon, or a planet to an object near its surface. (From NASA Thesaurus, 1988)
Motion of an object in which either one or more points on a line are fixed. It is also the motion of a particle about a fixed point. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Process that is gone through in order for a device to receive approval by a government regulatory agency. This includes any required preclinical or clinical testing, review, submission, and evaluation of the applications and test results, and post-marketing surveillance. It is not restricted to FDA.
Awareness of oneself in relation to time, place and person.
Freedom of equipment from actual or potential hazards.
Tumors or cancer of the DUODENUM.
The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.
Any infection which a patient contracts in a health-care institution.
A country in western Europe bordered by the Atlantic Ocean, the English Channel, the Mediterranean Sea, and the countries of Belgium, Germany, Italy, Spain, Switzerland, the principalities of Andorra and Monaco, and by the duchy of Luxembourg. Its capital is Paris.
Programs of disease surveillance, generally within health care facilities, designed to investigate, prevent, and control the spread of infections and their causative microorganisms.
Inflammatory responses of the epithelium of the URINARY TRACT to microbial invasions. They are often bacterial infections with associated BACTERIURIA and PYURIA.
Infection occurring at the site of a surgical incision.