Viral lysis of bacteria: an important source of dissolved amino acids and cell wall compounds
Middelboe, M.; Jørgensen, N.O.G. (2006). Viral lysis of bacteria: an important source of dissolved amino acids and cell wall compounds. J. Mar. Biol. Ass. U.K. 86(3): 605-612. https://dx.doi.org/10.1017/S0025315406013518 In: Journal of the Marine Biological Association of the United Kingdom. Cambridge University Press/Marine Biological Association of the United Kingdom: Cambridge. ISSN 0025-3154; e-ISSN 1469-7769, more |  |
| Authors | | Top | - Middelboe, M., more
- Jørgensen, N.O.G.
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| Abstract | Viral infection of bacteria causes release of dissolved organic matter (DOM), which is available for bacterial uptake. In aquatic environments, this virus-mediated transformation of living cells into dissolved and colloidal organic matter may be a quantitatively important process in the pelagic recycling of carbon and nutrients, but little is known about the amount, composition, or bioavailability of viral lysates. By using a model system of a marine bacterium (Cellulophaga sp.) and a virus specific to this bacterium, the present study provides a first quantification of the input of dissolved free and combined amino acids (DFAA and DCAA) and bacterial cell wall compounds following viral lysis. The DCAA constituted 51-86% of the total virus-mediated organic carbon release of 1087-1825 µg Cl-1 (estimated biomass of the lysed bacteria), whereas DFAA and glucosamine each accounted for 2-3% of total lysate-C. The viral particles themselves constituted 4-6% of the released organic carbon, and altogether, the applied analyses thus identified 53-92% of the released lysates. Approximately 12% of the identified compounds were derived from bacterial cell wall peptidoglycan, including various D-isomers of DFAA and DCAA, glucosamine and diaminopimelic acid (DAPA). Although a portion of this cell wall material may have entered the pool of refractory material, a significant fraction of some peptidoglycan-derived components, e.g. 83% of the released D-DFAA, were removed from the dissolved phase during the last part of the incubations, suggesting that part of the cell wall material were utilized by the developing virus-resistant Cellulophaga population. Therefore, we suggest that virus-mediated DOM is a source of a variety of organic compounds, which contribute significantly to the pool of rapidly recycling material in the ocean. |
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