Consequences of Thymidine Catabolism for Estimates of Bacterial Production: An Example from a Coastal Marine Sediment

Authors

Kevin R. Carman
Fred C. Dobbs, Old Dominion UniversityFollow
James B. Guckert

Document Type

Article

Publication Date

1988

DOI

10.4319/lo.1988.33.6part2.1595

Publication Title

Limnology and Oceanography

Volume

33

Issue

6

Pages

1595-1606

Abstract

Radioactively labeled thymidine (TdR) has been used extensively to measure bacterial production in aquatic environments, but critical assumptions of the TdR technique often have gone untested. In this study of a coastal marine sediment, the metabolic fate of methyl [³H]TdR and methyl [¹⁴C]TdR was at variance with the assumptions necessary for determining bacterial production. Only 2% of incorporated radioactivity was recovered in the DNA fraction of TCA-insoluble material following time-course incubations of l-300 min. At least the methyl group of TdR was extensively catabolized, as shown by copious production of ¹⁴C0₂. The temporal patterns of ³H : ¹⁴C ratios in macromolecular fractions indicated that products of catabolism were recycled into the DNA fraction. The accuracy of the TdR technique depends in large part on the degree to which such catabolism occurs.

Original Publication Citation

Carman, K. R., Dobbs, F. C., & Guckert, J. B. (1988). Consequences of thymidine catabolism for estimates of bacterial production: An example from a coastal marine sediment. Limnology and Oceanography, 33(6), 1595-1606. doi: 10.4319/lo.1988.33.6part2.1595

Repository Citation

Carman, Kevin R.; Dobbs, Fred C.; and Guckert, James B., "Consequences of Thymidine Catabolism for Estimates of Bacterial Production: An Example from a Coastal Marine Sediment" (1988). OES Faculty Publications. 143.
https://digitalcommons.odu.edu/oeas_fac_pubs/143