Production of dissolved DNA, RNA, and protein by microbial populations in a Florida reservoir

Journal Article · Mon Oct 01 04:00:00 EDT 1990 · Applied and Environmental Microbiology; (United States)

OSTI ID:5325118

Paul, J H; Jeffrey, W H; Cannon, J P ^[1]

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1. Univ. of South Florida, St. Petersburg (USA)

Production of dissolved macromolecules by ambient autotrophic and heterotrophic microbial populations was measured in a eutrophic Florida reservoir by in situ labeling with various radioactive substrates. When ({sup 3}H)thymidine was used as the precursor, production of labeled dissolved DNA, RNA, and protein was observed. In an attempt to specifically label phytoplankton DNA, samples were incubated with ({sup 3}H)adenine or {sup 32}P{sub i} in the presence and absence of the photosynthetic inhibitor 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU). Although DCMU inhibited {sup 14}C fixation by {approximately} 99%, this antimetabolite had only a slight effect on ({sup 3}H)adenine incorporation and no effect on {sup 32}P incorporation into cellular macromolecules. Significant amounts of dissolved DNA were produced in both ({sup 3}H)adenine and {sup 32}P{sub i} incubations, but again DCMU had no effect on the production rates. These results indicate that actively growing populations of both phytoplankton and bacterioplankton produced dissolved RNA and protein, while only active bacterioplankton produced measurable quantities of dissolved DNA. Dead or senescent phytoplankton may have produced dissolved DNA, but would not be measured in the relatively short incubations used. These findings also indicate that ({sup 3}H)adenine and {sup 32}P{sub i} primarily labeled heterotrophic bacterioplankton and not phytoplankton in this environment.

• OSTI ID: 5325118
• Journal Information: Applied and Environmental Microbiology; (United States), Journal Name: Applied and Environmental Microbiology; (United States) Vol. 56:10; ISSN 0099-2240; ISSN AEMID
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540311* -- Environment
Aquatic-- Basic Studies-- Radiometric Techniques-- (1990-)
ADENINES
AMINES
ANTIMETABOLITES
AQUATIC ORGANISMS
AROMATICS
AZAARENES
AZINES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL PATHWAYS
CARBON 14 COMPOUNDS
CARBON COMPOUNDS
CARBON CYCLE
DAYS LIVING RADIOISOTOPES
DEVELOPED COUNTRIES
DNA
DRUGS
ECOLOGY
ELEMENTS
FEDERAL REGION IV
FLORIDA
HETEROCYCLIC COMPOUNDS
HYDROGEN COMPOUNDS
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
LIGHT NUCLEI
NONMETALS
NORTH AMERICA
NUCLEI
NUCLEIC ACIDS
NUCLEOSIDES
NUCLEOTIDES
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHOSPHORUS
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
PLANKTON
PROTEINS
PURINES
PYRIMIDINES
RADIOISOTOPES
RIBOSIDES
RNA
SOLUTES
SURFACE WATERS
THYMIDINE
TRACER TECHNIQUES
TRITIUM COMPOUNDS
USA
WATER RESERVOIRS