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M A Foglesong

Publications and source records attributed to M A Foglesong.

7 recordsLinked to original sources
PubMed1984

Incorporation of amino acid-derived carbon into tylactone by Streptomyces fradiae GS14.

Washed cells from 72-h cultures of Streptomyces fradiae GS14 were used to examine the distribution of radiolabel from 14C-amino acids and related compounds into tylactone, CO2, and cells. Test compounds were categorized according to products of their oxidative degradation. Those compounds known to produce propionyl-coenzyme A by direct catabolic oxidation were designated as group I. Group II included those compounds oxidized to methylmalonyl-coenzyme A via succinyl-coenzyme A and the tricarboxylic acid cycle. Group III contained compounds known to be oxidized to acetoacetyl-coenzyme A. The total amount of label recovered after 60 min ranged from 3 to 65%. Although label from all test compounds except proline (group II) and lysine (group III) was incorporated into tylactone after 60 min, label from group I and group III compounds was incorporated at levels five times greater than label from group II compounds. From 55 to 75% of the recovered label from propionate (I), asparagine (II), glutamine (II), glutamate (II), alpha-ketoglutarate (II), and succinate (II) was recovered as 14CO2. From 75 to 95% of the recovered label from the remaining compounds tested was located in the cells. Based on the data, a pathway for the role of amino acids in the biosynthesis of tylactone is proposed.

Amino Acids↗
PubMed1984

Pleomorphism of fusobacteria isolated from the cockroach hindgut.

Fusobacteria are commonly isolated from the hindgut of the cockroach Eublaberus posticus . Eleven strains isolated from E. posticus by us were keyed to four species, Fusobacterium necrophorum, F. varium , F. gonidiaformans , and F. prausnitzii , using current taxonomic criteria. With the exception of F. gonidiaformis , all species showed rods with swollen centers and large bodies. The pleomorphism of F. varium was examined by phase microscopy and scanning and transmission electron microscopy. The pleomorphic process begins with a gradual swelling at the center of the rod until a large round body is formed. Some of these round bodies then fragment, giving rise to rod-shaped cells. When 10% yeast extract was added to growth media, pleomorphism was not induced. A dialyzable factor was found to account for this observation. Fermentation of [1-14C]glutamic acid gives rise to butyrate labeled in the carboxyl carbon, indicating that butyrate is formed by the hydroxyglutarate pathway which may be characteristic for the genus Fusobacterium.

Animals↗
PubMed1979

Possibility for error in FDA diffusion assays.

Computational procedures specified for the FDA single-dose diffusion assay for antibiotics may cause substantial error in estimated sample potency. An unrecognized mistake in reference solution concentration is the source of error. It is caused by correcting responses from standard and sample plates differently. The error can be avoided by correcting both standard and sample responses to the observed reference response.

Anti-Bacterial Agents↗
PubMed1978

Stability and blood level determinations of cefaclor, a new oral cephalosporin antibiotic.

Cefaclor solutions in pH 2.5 and 4.5 buffers contained at least 90% of their initial activity after 72 h at 4 degrees C. Samples in pH 6.0, 7.0, and 8.0 buffers contained 70, 46, and 34%, respectively, of their initial activity after 72 h at 4 degrees C. After 72 h at 25 degrees C, samples prepared with pH 2.5, 4.5, 6.0, 7.0, and 8.0 buffers contained 95, 69, 16, 5, and 3%, respectively, of their initial activity. After 72 h at 37 degrees C, cefaclor solutions in pH 2.5 buffer contained 80% of the initial activity, whereas samples prepared in pH 4.5, 6.0, 7.0, and 8.0 buffers contained less than 20%. Laboratory-prepared plasma and serum samples showed an 8% loss in activity when incubated for 6 h at 4 degrees C, a 51% loss when incubated for 6 h at 25 degrees C, and a 48% loss when incubated for 2 h at 37 degrees C. Clinical samples demonstrated a similar stability pattern. Degradation rates for cefaclor in commercially prepared serum increased from 4- to 10-fold in comparison to rates obtained when samples were made in human serum freshly prepared in our laboratory. Consequently, serum standards should be made in freshly prepared human serum.

Cephalosporins↗
PubMed1977

Stability of cephalosporins in horse serum.

The antibiotic activity of cephalothin, cephaloridine, cephalexin, cephaloglycin, cefazolin, and cefamandole was determined after storage for up to 30 days in horse serum at -10 and 4 degrees C. Cephalothin, cefamandole, cefazolin, and cephalexin were stable for at least 30 days at -10 degrees C, whereas cephaloridine lost 29% of its initial activity and cephaloglycin lost more than 50%. Cefamandole, cefazolin, and cephalexin could only be stored for 3 days at 4 degrees C without significant loss in activity, whereas cephalothin, cephaloridine, and cephaloglycin could be stored for only 1 day. Repeated freezing and thawing had a detrimental effect on the stability of cephaloridine.

Animals↗
PubMed1975

Ultrastructal morphology of some prokaryotic microorganisms associated with the hindgut of cockroaches.

Scanning electron microscopy and transmission electron microscopy have been used to visualize the morphology and ultrastructure of two types of microorganisms in the hindgut of the cockroach Blaberus posticus. Both organisms, designated as either short or long rods, are attached to chitinous projections from the gut wall. Micrographs suggest that the organisms are prokaryotic with a cell wall complex characteristic of gram-negative bacteria. However, certain differences were noted between the cell wall complex of the two types. Two forms of the long-rod type were noted, with one form appearing to be a "degenerate" or "transitional" cell. In the degenerate cells, vesicles are observed that often are contiguous with the cytoplasmic membrane. There are indications that the long-rod type may divide by longitudinal fission. Neither the short- nor long-rod type has been cultivated in its respective recognizable form.

Animals↗