In vivo metabolism of 2,2 prime -diaminopimelic acid from gram-positive and gram-negative bacterial cells by ruminal microorganisms and ruminants and its use as a marker of bacterial biomass

Journal Article · Sat Jun 01 00:00:00 EDT 1991 · Applied and Environmental Microbiology; (United States)

OSTI ID:5272300

Masson, H A; Denholm, A M; Ling, J R ^[1]

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1. Univ. College of Wales (United Kingdom)

Cells of Bacillus megaterium GW1 and Escherichia coli W7-M5 were specifically radiolabeled with 2,2{prime}-diamino (G-{sup 3}H) pimelic acid (({sup 3}H)DAP) as models of gram-positive and gram-negative bacteria, respectively. Two experiments were conducted to study the in vivo metabolism of 2,2{prime}-diaminopimelic acid (DAP) in sheep. In experiment 1, cells of ({sup 3}H)DAP-labeled B. megaterium GW1 were infused into the rumen of one sheep and the radiolabel was traced within microbial samples, digesta, and the whole animal. Bacterially bound ({sup 3}H)DAP was extensively metabolized, primarily (up to 70% after 8 h) via decarboxylation to ({sup 3}H)lysine by both ruminal protozoa and ruminal bacteria. Recovery of infused radiolabel in urine and feces was low (42% after 96 h) and perhaps indicative of further metabolism by the host animal. In experiment 2, ({sup 3}H)DAP-labeled B. megaterium GW1 was infused into the rumens of three sheep and ({sup 3}H)DAP-labeled E. coli W7-W5 was infused into the rumen of another sheep. The radioactivity contents of these mutant bacteria were insufficient to use as tracers, but the metabolism of DAP was monitored in the total, free, and peptidyl forms. Free DAP, as a proportion of total DPA in duodenal digesta, varied from 0 to 9.5%, whereas peptidyl DAP accounted for 8.3 to 99.2%.

• OSTI ID: 5272300
• Journal Information: Applied and Environmental Microbiology; (United States), Vol. 57:6; ISSN 0099-2240
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
BACILLUS
METABOLISM
BIOMASS
BIOLOGICAL MARKERS
ESCHERICHIA COLI
CELL CONSTITUENTS
CELL WALL
FECES
GASTROINTESTINAL TRACT
IN VIVO
MUTANTS
RUMINANTS
SHEEP
STOMACH
TRACER TECHNIQUES
TRITIUM COMPOUNDS
URINE
ANIMALS
BACTERIA
BIOLOGICAL MATERIALS
BIOLOGICAL WASTES
BODY
BODY FLUIDS
DIGESTIVE SYSTEM
DOMESTIC ANIMALS
ENERGY SOURCES
HYDROGEN COMPOUNDS
ISOTOPE APPLICATIONS
MAMMALS
MATERIALS
MICROORGANISMS
ORGANS
RENEWABLE ENERGY SOURCES
VERTEBRATES
WASTES
550201* - Biochemistry- Tracer Techniques