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1.
Int J Obes (Lond) ; 39(4): 549-56, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25504042

ABSTRACT

PURPOSE: Increasing evidence exists that maternal obesity (MO) and overnutrition during pregnancy and lactation have long-lasting consequences for progeny metabolism, cardiovascular and endocrine function. Data on effects of MO on offspring reproduction are limited. We hypothesized that MO during pregnancy and lactation in founder F(0) rat mothers would increase testicular and sperm oxidative stress (OS) and adversely impact male fertility in their F(1) offspring. METHODS: We induced pre-pregnancy MO by feeding F(0) females a high-fat diet from weaning through pregnancy and lactation. After weaning, all F(1) rats ate control (C) diet. We determined serum testosterone, malondialdehyde (MDA), reactive oxygen species (ROS) and superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity in F(1) testes and sperm at postnatal days (PNDs) 110, 450 and 650. RESULTS: At PNDs 450 and 650, MO offspring had lower luteinizing hormone while testosterone levels were lower at all ages. Testicular MDA and ROS concentrations and SOD and GPx activity were higher in MO F(1) at all ages. Nitrotyrosine immunostaining was higher at all ages in MO F(1) testes than C F(1). At PNDs 450 and 650, MO F(1) spermatozoa showed higher MDA concentrations and lower SOD and GPx activity with reduced sperm concentration, viability and motility, and more sperm abnormalities. Fertility rate was not affected at PND 110 but was lower in MO F(1) at PNDs 450 and 650. CONCLUSIONS: We conclude that MO during pregnancy and lactation increases F(1) testicular and sperm OS leading to premature aging of reproductive capacity.


Subject(s)
Fertility , Obesity/metabolism , Overnutrition/metabolism , Oxidative Stress , Pregnancy Complications/metabolism , Prenatal Exposure Delayed Effects/metabolism , Animal Nutritional Physiological Phenomena , Animals , Animals, Newborn , Diet, High-Fat , Female , Infertility/etiology , Lactation , Male , Maternal Nutritional Physiological Phenomena , Obesity/complications , Obesity/etiology , Overnutrition/complications , Pregnancy , Rats , Rats, Wistar , Sex Factors
3.
Front Physiol ; 2: 97, 2011.
Article in English | MEDLINE | ID: mdl-22194723

ABSTRACT

Several fecal steroid extraction techniques have been developed to measure the ovary function in different species of mammals. However, regardless of the method of extraction and the sample type chosen, it has been observed that they can yield results with different percentages of recuperation. The objective of this study was to determine whether the type of substratum, solvent and extraction method used have any influence on the extraction efficiency in the feces of Alouatta pigra (black howler monkey). For this purpose we used two methods: agitation and ebullition. With each method, we utilized moist and lyophilized feces. The validation of radioimmunoassay method was accurate and precise for quantify estradiol and progesterone in lyophilized feces of A. pigra. To both of which ethanol and methanol, absolute and at 80%, were added, besides the hormones (125)I-Estradiol and (125)I-Progesterone. The extraction efficiency for (125)I-Estradiol was from 87.72 ± 3.97 to 41.24 ± 2.67%, and for (125)I-Progesterone from 71.15 ± 4.24 to 42.30 ± 1.19% when we used the agitation method. Whereas with the ebullition method, the extraction efficiency for (125)I-Estradiol ranged from 86.89 ± 2.66 to 71.68 ± 3.02% and for (125)I-Progesterone from 98.31 ± 1.26 to 85.40 ± 1.98%. Due to the differences found in these assays, which depend on the method used, the type of feces employed and the type of solvent added to them, we recommend the ebullition method and the lyophilized feces of A. pigra for extracting the hormones, since in moist feces there may exist variables which might interfere in the quantification of (125)I-Estradiol and (125)I-Progesterone.

4.
Eur Respir J ; 37(3): 595-603, 2011 Mar.
Article in English | MEDLINE | ID: mdl-20530040

ABSTRACT

Ventilator-associated pneumonia (VAP) affects mortality, morbidity and cost of critical care. Reliable risk estimation might improve end-of-life decisions, resource allocation and outcome. Several scoring systems for survival prediction have been established and optimised over the last decades. Recently, new biomarkers have gained interest in the prognostic field. We assessed whether midregional pro-atrial natriuretic peptide (MR-proANP) and procalcitonin (PCT) improve the predictive value of the Simplified Acute Physiologic Score (SAPS) II and Sequential Related Organ Failure Assessment (SOFA) in VAP. Specified end-points of a prospective multinational trial including 101 patients with VAP were analysed. Death <28 days after VAP onset was the primary end-point. MR-proANP and PCT were elevated at the onset of VAP in nonsurvivors compared with survivors (p = 0.003 and p = 0.017, respectively) and their slope of decline differed significantly (p = 0.018 and p = 0.039, respectively). Patients with the highest MR-proANP quartile at VAP onset were at increased risk for death (log rank p = 0.013). In a logistic regression model, MR-proANP was identified as the best predictor of survival. Adding MR-proANP and PCT to SAPS II and SOFA improved their predictive properties (area under the curve 0.895 and 0.880). We conclude that the combination of two biomarkers, MR-proANP and PCT, improve survival prediction of clinical severity scores in VAP.


Subject(s)
Atrial Natriuretic Factor/blood , Calcitonin/blood , Gene Expression Regulation , Pneumonia, Ventilator-Associated/mortality , Protein Precursors/blood , Adult , Aged , Biomarkers/metabolism , Calcitonin Gene-Related Peptide , Female , Humans , Male , Middle Aged , Pneumonia, Ventilator-Associated/therapy , Prospective Studies , ROC Curve , Regression Analysis , Risk , Treatment Outcome
5.
J Physiol ; 563(Pt 1): 275-84, 2005 Feb 15.
Article in English | MEDLINE | ID: mdl-15611025

ABSTRACT

Nutrient restriction during pregnancy and lactation impairs growth and development. Recent studies demonstrate long-term programming of function of specific organ systems resulting from suboptimal environments during fetal life and development up to weaning. We determined effects of maternal protein restriction (50% control protein intake) during fetal development and/or lactation in rats on the reproductive system of male progeny. Rats were fed either a control 20% casein diet (C) or a restricted diet (R) of 10% casein during pregnancy. After delivery mothers received either C or R diet until weaning to provide four groups: CC, RR, CR and RC. We report findings in male offspring only. Maternal protein restriction increased maternal serum corticosterone, oestradiol and testosterone (T) concentrations at 19 days gestation. Pup birth weight was unchanged but ano-genital distance was increased by maternal protein restriction (P < 0.05). Testicular descent was delayed 4.4 days in RR, 2.1 days in CR and 2.2 days in RC and was not related to body weight. Body weight and testis weight were reduced in RR and CR groups at all ages with the exception of CR testis weight at 270 days postnatal age (PN). At 70 days PN luteinizing hormone and T concentrations were reduced in RR, CR and RC. mRNA for P450 side chain cleavage (P450scc) was reduced in RR and CR at 21 days PN but was unchanged at 70 days PN. Fertility rate was reduced at 270 days PN in RC and sperm count in RR and RC. We conclude that maternal protein delays sexual maturation in male rats and that some effects only emerge in later life.


Subject(s)
Diet, Protein-Restricted/methods , Fertility/physiology , Genitalia, Male/growth & development , Lactation/physiology , Maternal-Fetal Exchange/physiology , Pregnancy, Animal/physiology , Sexual Development/physiology , Animals , Animals, Newborn , Female , Male , Pregnancy , Rats , Rats, Wistar
6.
Am J Reprod Immunol ; 29(4): 219-23, 1993 May.
Article in English | MEDLINE | ID: mdl-8397811

ABSTRACT

The effect of estradiol (E2) and progesterone (P4) on the IgA system, both at the systemic and at the mucosal level, was studied in 10 healthy young adult Mexican women during two consecutive menstrual cycles (MC); the control group consisted of five young adult Mexican men. Eight matched samples of blood and parotid saliva were obtained, in which serum E2, P4, and IgA were quantified. Parotid saliva was obtained with Curby's device and sIgA was quantified by an ELISA method. The MC was divided into follicular phase (FP, days 1 to 16) and luteal phase (LP, days 17 to 30). Serum IgA showed slight fluctuations along the period of study, but they were not different between women and men. Irrespective of the phase of the MC, salivary sIgA was higher in women than in men (P < 0.01); sIgA was slightly but not significantly higher in the FP, as compared to the LP. The comparison of phases in each individual woman showed significantly higher levels in the FP (P < 0.01). The profile of sIgA in saliva observed in women resembled the pattern of serum E2 (r = 0.859, P < 0.05), suggesting a possible relation of E2 in the secretion of sIgA by the parotid gland.


Subject(s)
Estradiol/blood , Immunoglobulin A, Secretory/metabolism , Menstrual Cycle/immunology , Progesterone/blood , Adolescent , Adult , Female , Follicular Phase/immunology , Follicular Phase/metabolism , Humans , Immunoglobulin A/blood , Luteal Phase/immunology , Luteal Phase/metabolism , Male , Menstrual Cycle/metabolism , Parotid Gland/immunology , Saliva/immunology
8.
J Antibiot (Tokyo) ; 45(9): 1499-511, 1992 Sep.
Article in English | MEDLINE | ID: mdl-1429236

ABSTRACT

The biosynthetic origin of antibiotic A10255 was investigated using 14C- and 13C-labeled amino acids. DL-[1-(13)C]Serine labeled 15 of the 17 amino acid residues present in A10255G. These included the oxazole, thiazole, dehydroalanine, masked glycine, masked alanine and pyridine moieties. The same 15 residues labeled by serine were labeled by [2-(13)C]glycine, apparently by conversion of the glycine to [2,3-(13)C]serine. Formation of the pyridine ring occurred via a C3 to C3 condensation of two serines. The results indicated origin of the masked alanine from alanine; the masked glycine from glycine; the thiazole residues from cysteine; and the threonine, masked dehydrobutyrine, masked dehydronorvaline and masked dehydroleucine residues from threonine. L(-)[CH3-(13)C]Methionine labeled the methyl carbon of the masked dehydronorvaline moiety in factor B and the two methyl carbons of the masked dehydroleucine moiety in factor E. The results demonstrate that A10255 originates exclusively from amino acids in a manner similar to the closely related thiopeptide antibiotics nosiheptide and thiostrepton.


Subject(s)
Anti-Bacterial Agents , Anti-Bacterial Agents/biosynthesis , Peptides, Cyclic/biosynthesis , Peptides , Amino Acid Sequence , Amino Acids/metabolism , Anti-Bacterial Agents/analysis , Anti-Bacterial Agents/chemistry , Cells, Cultured , Chromatography, High Pressure Liquid , Magnetic Resonance Spectroscopy , Molecular Sequence Data , Peptides, Cyclic/analysis , Peptides, Cyclic/chemistry
9.
J Antibiot (Tokyo) ; 45(8): 1222-30, 1992 Aug.
Article in English | MEDLINE | ID: mdl-1399842

ABSTRACT

A10255 is a complex of new thiopeptide antibiotics characterized structurally by a cyclic peptide core to which is attached a side chain composed of dehydroalanine moieties. The complex contained 80-85% factor B, 15-20% factor G, and trace amounts of factors C, D, E, F, H, and J. Taxonomic studies indicated the producing microorganism to be a strain of Streptomyces gardneri. The major portion of the antibiotic produced remained associated with the mycelial biomass, from which it was extracted with polar solvents such as aqueous methanol or aqueous acetone. Initial A10255 yields of < 2 micrograms/ml were increased to over 300 micrograms/ml in stirred reactors through strain selection, nutritional studies, and conversion of the batch fermentation to a fed-batch mode.


Subject(s)
Anti-Bacterial Agents , Anti-Bacterial Agents/isolation & purification , Growth Substances/isolation & purification , Peptides, Cyclic/isolation & purification , Peptides , Streptomyces/metabolism , Anti-Bacterial Agents/biosynthesis , Fermentation , Peptides, Cyclic/pharmacology , Streptomyces/classification
10.
J Antibiot (Tokyo) ; 45(8): 1278-85, 1992 Aug.
Article in English | MEDLINE | ID: mdl-1399849

ABSTRACT

A10255 is a complex of new thiopeptide antibiotics produced by Streptomyces gardneri. When stirred reactors were operated in batch mode using a defined medium with a glucose feed, 250 micrograms/ml of A10255 were produced during a four-day fermentation cycle. The linear growth phase of S. gardneri was extended through seven days by supplementing the defined medium with continuous feeds of hydrolyzed casein and methyl caprate. With the supplementary feeds, antibiotic biosynthesis paralleled growth during the extended cycle and attained levels of 1,750 micrograms/ml. Increasing the standard glucose feed rate increased titers principally by increasing cell mass. Supplementing the standard glucose feed with lipids such as caprylate or caprate, and decyl alcohol, affected cell mass minimally but produced higher titers by increasing the specific biosynthesis of A10255 per unit of biomass.


Subject(s)
Anti-Bacterial Agents/biosynthesis , Peptides, Cyclic/biosynthesis , Peptides , Streptomyces/metabolism , Culture Media , Glucose/metabolism , Lipid Metabolism , Nitrogen/metabolism
11.
J Antibiot (Tokyo) ; 45(4): 433-43, 1992 Apr.
Article in English | MEDLINE | ID: mdl-1592675

ABSTRACT

A new member of the aurodox family of antibiotics, A83016F, has been isolated from an unidentified actionmycete designated A83016. The structure and relative stereochemistry of A83016F were elucidated by NMR examination of the parent compound and its diacetate derivative. A83016F exhibits only weak antimicrobial activity.


Subject(s)
Actinomyces/chemistry , Aurodox/analogs & derivatives , Aurodox/isolation & purification , Anti-Bacterial Agents , Aurodox/chemistry , Aurodox/pharmacology , Bacteria/drug effects , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Microbiological Techniques , Molecular Weight , Stereoisomerism
12.
Contraception ; 43(1): 45-53, 1991 Jan.
Article in English | MEDLINE | ID: mdl-2004528

ABSTRACT

A solid dispersion of ethinylestradiol-cholesterol (EE & CHOL; eutectic 1:4 W/W) was prepared by melting and rapid cooling. The fused material was then mixed with lactose as vehicle. Soft gelatin capsules were filled with 50 mg of the final mixture to give 0.050 mg of ethinylestradiol. Six female volunteers received, one capsule of the eutectic combination of EE:CHOL or one 50 micrograms tablet of ethinylestradiol (Dianor, Syntex), in a cross-over study and in fasting state. Venous blood samples were drawn at 0, 10, 20, 30, 40, 50, 60, 90, 120, 240, 360, 480, 720, 1440 minutes after dosing. Immunoreactive EE was measured by radioimmunoassay to assess the serum concentration-time course. All subjects exhibited a significant increase in EE levels after oral administration. Mean peak EE levels, 1350 pg/ml vs 91 pg/ml (p less than 0.001), were achieved 360 minutes and 90 minutes (p less than 0.01), after administration of the eutectic and reference formulation, respectively. Eutectic mixture showed a greater area under the serum concentration-time curve, longer mean residence time of the drug in the body, and four times the value of the elimination half-life of the reference formulation. It is concluded that the combination of ethinylestradiol with cholesterol forming an eutectic mixture, when administered orally to normal women, modulates the absorption and the bioavailability of the EE. This approach may be suitable for long-acting oral treatment with sex steroids.


Subject(s)
Cholesterol , Ethinyl Estradiol/metabolism , Intestinal Absorption/drug effects , Administration, Oral , Adult , Biological Availability , Cholesterol/pharmacology , Ethinyl Estradiol/administration & dosage , Ethinyl Estradiol/blood , Fasting , Female , Humans , Radioimmunoassay
13.
J Antibiot (Tokyo) ; 43(6): 587-93, 1990 Jun.
Article in English | MEDLINE | ID: mdl-2380106

ABSTRACT

A54145 is a complex of new lipopeptide antibiotics that inhibits Gram-positive bacteria and acts as a growth promotant for broiler chicks. Eight factors; A, B, C, D, E, F, A1 and B1; have been isolated and characterized. They contain four similar peptide nuclei, each of which is acylated with either an 2-decanoyl, n-decanoyl, or undecanoyl side chain. Taxonomic studies ascertained that the producing microorganism was a strain of Streptomyces fradiae. Fermentation studies determined that superior antibiotic yields were obtained in stirred bioreactors in a soybean flour-molasses medium employing a continuous glucose feed. These findings, interwoven with the selection of hyper-productive mutants, increased fermentation yields from less than 50 micrograms/ml to more than 1 mg/ml. An analytical HPLC system was developed for the identification and subsequent quantitation of each factor of the A54145 complex.


Subject(s)
Anti-Bacterial Agents/biosynthesis , Soil Microbiology , Streptomyces/metabolism , Amino Acid Sequence , Animals , Anti-Bacterial Agents/analysis , Chromatography, High Pressure Liquid , Fermentation , Lipoproteins/analysis , Lipoproteins/biosynthesis , Molecular Sequence Data , Streptomyces/classification
14.
J Antibiot (Tokyo) ; 43(6): 607-15, 1990 Jun.
Article in English | MEDLINE | ID: mdl-2380109

ABSTRACT

A54145 is a complex of new lipopeptide antibiotics produced by Streptomyces fradiae. Eight factors, containing four similar peptide nuclei in combination with three different fatty acid acyl side chains, have been isolated from the natural fermentation and characterized. The nuclei differ only in valine/isoleucine and glutamate/3-CH3-glutamate substitutions at one or both of two locations on the peptide ring. Prior deacylation of all four nuclei with Actinoplanes utahensis had permitted chemical reacylation of each nucleus with new fatty acid acyl chains for structure-activity relationship studies. In an effort to induce the native biosynthesis of preferred factors or analogs by S. fradiae, the effect of fatty acid precursors on the fermentation was examined. Many fatty acids were extremely toxic to S. fradiae, which limited experiments to slow, continuous feeding of the lipids in stirred bioreactors that were equipped for on-line respiration analysis by mass spectrometry. These studies determined that precursing with aliphatic fatty acids of various chain lengths did enhance the biosynthesis of factors containing specific fatty acid acyl side chains. Caprate, for example, increased the n-decanoyl-containing factors from the natural level of approximately 14% to approximately 80%. The percentage of factors containing branched-chain fatty acid acyl substituents was also increased, in shaken-flask studies, by enriching the medium with valine or isoleucine. These amino acids additionally enhanced the percentage of nuclei containing either valine or isoleucine.


Subject(s)
Anti-Bacterial Agents/biosynthesis , Streptomyces/metabolism , Amino Acid Sequence , Caprylates/metabolism , Decanoic Acids/metabolism , Fatty Acids/metabolism , Fermentation , Laurates/metabolism , Lipid Metabolism , Lipoproteins/biosynthesis , Molecular Sequence Data , Molecular Structure , Oxygen Consumption
15.
J Antibiot (Tokyo) ; 43(6): 623-33, 1990 Jun.
Article in English | MEDLINE | ID: mdl-1696251

ABSTRACT

New semi-naphthaquinone antibiotics A80915A, B, C, and D were isolated from the fermented broth of Streptomyces aculeolatus A80915 (NRRL 18422). Factors A and C, present in both the broth filtrate and mycelial methanol extract, and factors B and D, found predominantly in the broth filtrate, were recovered by extraction with ethyl acetate. Purification of the individual factors was accomplished by preparative reverse phase high performance liquid chromatograph on C18 bonded silica supports. Factors A through D show antimicrobial activity against Gram-positive aerobic and anaerobic organisms in vitro. Mechanism of action studies demonstrated nearly complete inhibition of macromolecular biosynthesis (protein, RNA, DNA, and cell wall) by A80915 factors A through D. A less highly cyclized semi-naphthaquinone, A80915 factor G, was isolated from the broth of the strain fermented in an alternate medium.


Subject(s)
Anti-Bacterial Agents/biosynthesis , Bacteria/drug effects , Soil Microbiology , Streptomyces/metabolism , Animals , Anti-Bacterial Agents/analysis , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Bacteria/genetics , Bacteria/metabolism , Bacterial Proteins/biosynthesis , Bacterial Proteins/drug effects , Chromatography, High Pressure Liquid , DNA, Bacterial/biosynthesis , DNA, Bacterial/drug effects , Fermentation , Mice , Microscopy, Electron, Scanning , Molecular Structure , Naphthoquinones/analysis , Naphthoquinones/isolation & purification , Naphthoquinones/metabolism , Naphthoquinones/pharmacology , RNA, Bacterial/biosynthesis , RNA, Bacterial/drug effects , Staphylococcal Infections/drug therapy , Streptococcal Infections/drug therapy , Streptomyces/classification , Streptomyces/ultrastructure
17.
J Antibiot (Tokyo) ; 42(3): 382-8, 1989 Mar.
Article in English | MEDLINE | ID: mdl-2708131

ABSTRACT

Echinocandin B (ECB) is a lipopeptide antifungal agent produced by several species of Aspergillus. The lipid side chain of cyclic lipopeptides is known to be an important determinant of their antibiotic activity and toxicity. Deacylation of another lipopeptide antibiotic, A21978C, had formerly been accomplished with Actinoplanes utahensis. In spite of the structural dissimilarities between the peptide cores and acyl side chains of A21978C and ECB, A. utahensis also removed the linoleoyl acyl unit from the amino terminus of ECB to yield the bioinactive cyclic peptide core, or "nucleus". The ECB nucleus, which contained a new titratable group at the N-terminus, was subsequently employed for chemical reacylation with other side chains to yield a variety of novel ECB analogs. One of these, cilofungin (LY121019), containing an N-(4-n-octyloxybenzoyl)acyl unit, is currently undergoing clinical evaluation.


Subject(s)
Actinomycetales/metabolism , Anti-Bacterial Agents , Antifungal Agents/metabolism , Fungal Proteins , Peptides, Cyclic , Acylation , Drug Stability , Echinocandins , Hydrogen-Ion Concentration , Peptides/metabolism , Solubility
18.
J Antibiot (Tokyo) ; 41(9): 1170-7, 1988 Sep.
Article in English | MEDLINE | ID: mdl-3182398

ABSTRACT

16-Deethylindanomycin (A83094A) is a novel pyrrole-ether antibiotic produced by a strain of Streptomyces setonii. The antibiotic, which is structurally similar to indanomycin (X-14547A), is active in vitro against Gram-positive bacteria as well as coccidia.


Subject(s)
Anti-Bacterial Agents/isolation & purification , Streptomyces/metabolism , Animals , Anti-Bacterial Agents/biosynthesis , Coccidia/drug effects , Fermentation , Gram-Positive Bacteria/drug effects , Indenes/biosynthesis , Indenes/isolation & purification , Indenes/pharmacology , Mice , Pyrans/biosynthesis , Pyrans/isolation & purification , Pyrans/pharmacology , Streptomyces/classification
19.
J Antibiot (Tokyo) ; 41(8): 1085-92, 1988 Aug.
Article in English | MEDLINE | ID: mdl-3170344

ABSTRACT

A21978C, produced by Streptomyces roseosporus NRRL 11379, is an acidic lipopeptide antibiotic complex that inhibits Gram-positive bacteria. Individual factors of the complex possess an identical peptide core or "nucleus", and are differentiated by the distinctive fatty acid acyl group attached to the N-terminus of the nucleus. Certain members of the family Actinoplanaceae deacylated A21978C to yield the unaltered nucleus, which was then reacylated to form new analogs. Actinoplanes utahensis NRRL 12052 was the most efficient of these cultures, producing up to 500 micrograms of nucleus per ml of culture broth per hour. Eacylation was also accomplished with semi-pure and tert-butoxycarbonyl (tert-BOC)-A21978C. In the latter, the ornithine amino group was blocked to prevent formation of diacyl analogs during reacylation. The acylase was an endoenzyme present in submerged cultures of A. utahensis from less than 18 to greater than 168 hours of incubation. Whole cells suspended in phosphate buffer or entrapped in polyacrylamide gel also deacylated A21978C efficiently.


Subject(s)
Actinomycetales/metabolism , Anti-Bacterial Agents/metabolism , Peptides , Acylation , Amidohydrolases/metabolism , Hydrogen-Ion Concentration , Intercellular Signaling Peptides and Proteins , Peptides, Cyclic/metabolism , Streptomyces/metabolism
20.
J Antibiot (Tokyo) ; 41(6): 726-33, 1988 Jun.
Article in English | MEDLINE | ID: mdl-3403366

ABSTRACT

A culture identified as Streptomyces karnatakensis was found to produce a novel cyclic hexadepsipeptide antibiotic designated A83586C. The structure was elucidated by X-ray crystallography, and full 1H and 13C NMR assignments are reported. The absolute configuration was confirmed by the detection of D-threonine in the acid hydrolysate of A83586C. A83586C had potent Gram-positive activity in vitro but lacked in vivo efficacy in mice.


Subject(s)
Anti-Bacterial Agents , Anti-Bacterial Agents/isolation & purification , Depsipeptides , Peptides , Animals , Anti-Bacterial Agents/pharmacology , Fermentation , Mice , Molecular Conformation , Peptides, Cyclic/isolation & purification , Streptomyces/classification , Streptomyces/metabolism
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