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PubMed1987

The growth and nutrition of Clostridium sporogenes NCIB 8053 in defined media.

Various defined and minimal media are described for the growth of Clostridium sporogenes NCIB 8053. The organism requires 10 amino acids and one vitamin for growth, whilst three other vitamins are growth stimulatory. L-alpha-hydroxy acid analogues can replace eight, and fatty acid analogues four, of these amino acids. The organism may generate free energy by a variety of Stickland reactions. Most Stickland acceptors, but not glycine, stimulate the growth of this organism on glucose. Nonetheless, cells grown in the presence of glycine will reductively deaminate it. The media described support the growth of several other strains of this species. The simplified growth media which we have developed permit quantitative studies of the physiology of this organism.

Acetates↗
PubMedDate not supplied

Erythrokeratoderma variabilis successfully treated with topical tazarotene.

Erythrokeratoderma variabilis, also known as Mendes da Costa syndrome, is a genodermatosis belonging to the group of diseases known as the erythrokeratodermias. Erythrokeratoderma variabilis is characterized by two distinctive manifestations: well-demarcated, variable, transient, figurate patches of erythema, and localized or generalized hyperkeratotic plaques. Treatments include topical retinoic acid, salicylic acid, and alpha-hydroxy acid in petrolatum, but all have been reported to have limited, variable success rates. We report a child with erythrokeratoderma variabilis with no family history of this entity, successfully treated with topical tazarotene.

Child, Preschool↗
PubMed1982

Activity of metronidazole and its hydroxy and acid metabolites against clinical isolates of anaerobic bacteria.

Susceptibility of clinical isolates of anaerobic bacteria to metronidazole and its two oxidation products, 1-(2-hydroxyethyl)-2-hydroxymethyl-5-nitroimidazole (the "alcohol" metabolite) and 2-methyl-5-nitroimidazole-1-acetic acid (the "acid" metabolite), were determined by the agar dilution technique. Results disclosed that the alcohol metabolite, although less active than metronidazole, inhibited the organisms tested at levels considered susceptible for metronidazole. The acid metabolite was less active, not inhibiting the organisms at levels within the susceptible range. In other studies, mixtures of known concentrations of metronidazole and the metabolites were assayed in a bioassay system used to measure metronidazole levels. These studies showed that the bioassay will measure metronidazole or the alcohol metabolite; the acid metabolite is not measured at levels achieved in clinical specimens. Since the activity of the alcohol metabolite is comparable to that of metronidazole, we feel that microbiological assays can be used for therapeutic monitoring of metronidazole levels in clinical situations.

Anaerobiosis↗
PubMed1979

Hydroxy amino acid metabolism in Pseudomonas cepacia: role of L-serine deaminase in dissimilation of serine, glycine, and threonine.

Growth of Pseudomonas cepacia (P. multivorans) on serine depended upon induction of a previously undescribed L-serine deaminase distinct from threonine deaminase. Formation of the enzyme was induced during growth on serine, glycine, or threonine. The induction pattern reflected a role of the enzyme in catabolism of these three amino acids. Both threonine and glycine supported growth of serine auxotrophs and were presumably converted to serine and pyruvate in the course of their degradation. Mutant strains deficient in serine deaminase, or unable to use pyruvate as a carbon source, failed to utilize serine or glycine and grew poorly with threonine, whereas strains deficient in threonine dehydrogenase or alpha-amino beta-ketobutyrate:coenzyme A ligase (which together convert threonine to glycine and acetyl coenzyme A) failed to utilize threonine or derepress serine deaminase in the presence of this amino acid. The results confirm for the first time the role of alpha-amin beta-ketobutyrate:coenzyme A ligase in threonine degradation and indicate that threonine does not mimic serine as an inducer of serine deaminase.

Amino Acid Oxidoreductases↗
PubMed1990

Surface-active novel glycolipid and linked 3-hydroxy fatty acids produced by Serratia rubidaea.

A Serratia rubidaea isolate with wetting activity when grown at 30 but not 37 degrees C was examined for the production of specific lipids. Two novel lipids (rubiwettins R1 and RG1) were isolated and shown to be able to lower the surface tension of saline to 26 mN/m. These lipids were located in extracellular vesicles found in a 30 degrees C culture of S. rubidaea. Chemical structures of these biosurfactants were determined by degradation product analyses, infrared spectroscopy, mass spectrometry, and proton nuclear magnetic resonance spectroscopy. Rubiwettin R1 was proposed to be a mixture of 3-(3'-hydroxytetradecanoyloxy)decanoate, 3-(3'-hydroxyhexadecenoyloxy)decanoate, and minor molecular isomers. The structure of rubiwettin RG1 was proposed to be beta-D-glucopyranosyl 3-(3'-hydroxytetradecanoyloxy)decanoate. The importance of such surface-active exolipids in bacterial occupancy on surfaces was suggested.

Chromatography, Thin Layer↗
PubMed1993

Hydroxy-fatty acid profiles of Legionella species: diagnostic usefulness assessed by principal component analysis.

Twenty-nine species (76 strains) of members of the genus Legionella were analyzed for their cellular hydroxylated fatty acids (OH-FAs). The individual patterns were unusually complex and included both monohydroxylated and dihydroxylated chains of unbranched or branched (iso and anteiso) types. Comparison of the strain profiles by SIMCA (Soft Independent Modelling of Class Analogy) principal component analysis revealed four main groups. Group 1 included Legionella pneumophila plus L. israelensis strains, and group 2 included L. micdadei and L. maceacherneii strains. These two closely related groups were characterized by the occurrence of di-OH-FAs and differed mainly in the amounts of 3-OH-a21:0, 3-OH-n21:0, 3-OH-n22:0, and 3-OH-a23:0. Group 3 (13 species) was distinguished by i14:0 at less than 3%, 3-OH-3-OH-n14:0 at greater than 5%, 3-OH-n15:0 at greater than 2%, and minute amounts of OH-FAs with chains longer than 21:0. Group 4 (12 species) was heterogeneous. Its main characteristics were the presence of 3-OH-n12:0 and 3-OH-n13:0, 3-OH-i14:0 at greater than 5%, as well as significant amounts of 3-OH-a21:0 and 3-OH-n21:0. The groupings obtained by OH-FA profiles were found to reflect DNA-DNA homology groupings reasonably well, and the profiles appear to be useful for differentiation of Legionella species.

DNA, Bacterial↗
PubMed1969

Congenital dysfibrinogenemia: fibrinogen Detroit.

A 17 yr old female with a congenital bleeding disorder was found to suffer from dysfibrinogenemia. Whole blood and plasma coagulation times were delayed and thrombelastograms were grossly abnormal. Clottability of plasma fibrinogen by addition of thrombin was not demonstrated during the 30 min test period. Fibrinogen was revealed by turbidometric and immunologic techniques. Other coagulation factors were present in normal amounts and prothrombin activation was normal. Patient's plasma inhibited thrombin clotting times of normal plasma and purified normal fibrinogen. Fibrinolysis was not detected. The plasma fibrinogen migrated normally on paper and cellulose acetate electrophoresis, but on immunoelectrophoresis it displayed a faster mobility than normal fibrinogen. On immunodiffusion the antigenic determinants were similar to those of normal fibrinogen. The patient's fibrinogen-antifibrinogen precipitins required longer to appear and the resultant precipitin was broader and hazier than those elicited with normal fibrinogen. These findings suggest the presence of two discrete populations of fibrinogen molecules. Investigation of the family of the patient suggested that the defect has an autosomal dominant pattern of heredity. Immunologic comparisons of our patient's plasma and of her relatives with plasma of patients with "Fibrinogen Baltimore" and "Fibrinogen Cleveland" revealed certain differences in immunoelectrophoretic mobility as well as in immunodiffusion. In keeping with the nomenclatures of abnormal fibrinogens in the literature, we propose the term "Fibrinogen Detroit" for this fibrinogen.Physicochemical properties of "Fibrinogen Detroit" were investigated also and compared with those of normal fibrinogen. Purified normal fibrinogen (clottability 96.7%) and "Fibrinogen Detroit" revealed homogeneity when studied by ultracentrifugation and immunoelectrophoresis. Native and cleaved "Fibrinogen Detroit" had the same sedimentation constants and molecular weights as the normal. In fresh samples. 3 moles of free SH groups/mole of fibrinogen were titrated in both. Determination of the amino acid composition revealed a decreased content of lysine, glucosamine, and galactosamine in abnormal fibrinogen. Total carbohydrates, protein-bound hexoses, sialic acid, and hexosamine were decreased in the abnormal fibrinogen. In an investigation with Doctors Blombäck a specific molecular defect was revealed in the N-terminal disulfide knot of the alpha (A) chain in which the arginine at the 19th position was replaced by serine. It is believed that the substitution of a strongly basic amino acid with a neutral hydroxy acid may result in considerable conformational changes in the N-terminal disulfide knot of fibrinogen which might affect the "active site" for polymerization. The lower carbohydrate content observed in "Fibrinogen Detroit" may have been the result of a change in primary and tertiary structure of the protein.

Adolescent↗