Gut bacteria recycle uric acid nitrogen in termites: A strategy for nutrient conservation
| Autor: | Catherine J. Potrikus, John A. Breznak |
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| Rok vydání: | 1981 |
| Předmět: | |
| Zdroj: | Proceedings of the National Academy of Sciences. 78:4601-4605 |
| ISSN: | 1091-6490 0027-8424 |
| DOI: | 10.1073/pnas.78.7.4601 |
| Popis: | Reticulitermes flavipes termites synthesize uric acid via purine-nucleoside phosphorylase (purine-nucleoside: orthophosphate ribosyltransferase, EC 2.4.2.1) and xanthine dehydrogenase (xanthine:NAD + oxidoreductase, EC 1.2.1.37), but their tissues lack uricase (urate:oxygen oxidoreductase, EC 1.7.3.3) or any other enzyme that degrades uric acid. Nevertheless, uricolysis occurs in termites, but as an anaerobic process mediated by hindgut bacteria. 14 C-Tracer experiments showed that termites transport uric acid from the site of synthesis and storage (fat body tissue) to the site of degradation (hindgut microbiota) via Malpighian tubules. Moveover, [1,3- 15 N]uric acid dissimilated by gut bacteria in vivo leads to assimilation of 15 N into termite tissues. NH 3 , a product of uricolysis, is a potential N source for termites, either directly via glutamine synthetase [L-glutamate:ammonia ligase (ADP-forming), EC 6.3.1.2] activity of fat body tissue or indirectly through microbe assimilation. Symbiotic recycling of uric acid N appears to be important to N conservation in these oligonitrotrophic insects. |
| Databáze: | OpenAIRE |
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