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L D Kennedy

Publications and source records attributed to L D Kennedy.

26 records · Page 2Linked to original sources
PubMed1974

Teichoic acid synthesis in Bacillus stearothermophilus.

1. Particulate enzyme preparations obtained from Bacillus stearothermophilus B65 by digestion with lysozyme were shown to catalyse teichoic acid synthesis. With CDP-glycerol as sole substrate the preparations synthesized 1,3-poly(glycerol phosphate). It was characterized by alkaline hydrolysis, by glucosylation to the alkali-stable 2-glucosyl-1,3-poly(glycerol phosphate) with excess of UDP-glucose and a Bacillus subtilis Marburg enzyme system, by degradation of this latter product with 60%HF and periodate oxidation of the resulting glucosylglycerol. The specificity of the B. subtilis system previously reported (Glaser & Burger, 1964), was confirmed in the present work. 2. Pulse-labelling experiments, followed by periodate oxidation of the product and isolation of formaldehyde from the glycerol terminus of the polymer, showed that the B. stearothermophilus enzyme system transferred glycerol phosphate units to the glycerol end of the chain. The transfer reaction was irreversible. It was not determined if these poly(glycerol phosphate) chains were synthesized de novo, but it was shown that the newly synthesized oligomers were bound to much larger molecules. 3. When the B. stearothermophilus enzyme system was supplied with both CDP-glycerol and UDP-glucose, 1-glucosyl-2,3-poly(glycerol phosphate) was synthesized in addition to the 1,3-isomer. The former polymer was characterized by acid and alkaline hydrolysis, degradation with HF and periodate oxidation of the resulting glucosylglycerol, and periodate oxidation of the intact polymer followed by mild acid hydrolysis. This latter procedure removed the glucose substituents without disrupting the poly(glycerol phosphate) chain. 4. The poly(glycerol phosphate) isomers were distinguished by glucosylation with the B. subtilis enzymes and alkaline hydrolysis, the 2,3-isomer remaining alkali-labile. The proportion of 2,3-poly(glycerol phosphate) in the product increased with increasing amounts of UDP-glucose in the incubation mixture, but the total glycerol phosphate incorporated into products remained constant. It is suggested that the synthetic pathways of the two poly(glycerol phosphate) species may share a rate-limiting step.

Bacillus↗
PubMedDate not supplied

Prevention and treatment of veno-occlusive disease.

OBJECTIVE: To review the current options for prevention and treatment of veno-occlusive disease in bone marrow transplant patients. DATA SOURCES: Articles were selected from a MEDLINE search (1966-October 1999) using the key terms veno-occlusive disease and bone marrow transplantation. In addition, references of all articles were examined for articles not found in the computer-based search. DATA EXTRACTION: All clinical trials, case-control studies, and case reports were evaluated. RESULTS: Heparin, low-molecular-weight heparin, prostaglandin E1, ursodiol, and glutamine have been studied for prevention of veno-occlusive disease. Heparin has been studied most extensively; however, no preventive regimen has a defined role in therapy. For treatment, tissue plasminogen activator has been evaluated most thoroughly, yet its safety and efficacy have not been clearly established in patients with veno-occlusive disease. Other possible treatment options include antithrombin-III, defibrotide, glutamine plus vitamin E, and surgery. CONCLUSIONS: Based on the available data, the most promising agents are ursodiol for prevention and defibrotide or glutamineplus vitamin E for treatment of veno-occlusive disease. Further clinical trials are needed to establish the appropriate preventive and treatment options available for bone marrow transplant patients suffering from veno-occlusive disease. To date, such decisions depend largely on poorly designed trials, case reports, and clinical experience.

Anticoagulants↗