Biology Department, Dalhousie University, Halifax, Nova Scotia B3H 4J1, Canada.
Appl Environ Microbiol. 1986 Sep;52(3):504-9. doi: 10.1128/aem.52.3.504-509.1986.
The availability of dead microbial biomass in a marine beach sand to degradation and mineralization was examined. Microbial sand populations were labeled with [C]glutamic acid, [H]adenine, or [H]thymidine and killed with chloroform. Live sand or seawater (or both) was added to the sterile labeled sand, and biochemical components of the populations were monitored for 10 days. Labeled RNA was degraded more quickly than labeled DNA, but both nucleic acids were degraded to approximately the same extent (60 to 70%). H(2)O was a major acid-soluble breakdown product. RNA (and possibly DNA) breakdown products were reincorporated into DNA (and possibly RNA) during the incubation period. In addition to metabolite salvage, 32% of the total macromolecular C was respired in the 10-day period regardless of whether sand or seawater was used as the inoculum. Respiration was essentially complete in 3 days, whereas nucleic acid degradation continued throughout the 10-day incubation. The results indicate that dead microbial biomass is a labile component of the sediment ecosystem.
本文研究了海洋沙滩砂中死亡微生物生物量的降解和矿化可用性。用 [C]谷氨酸、[H]腺嘌呤或 [H]胸腺嘧啶对微生物砂种群进行标记，并用氯仿杀死。将无菌标记砂与活砂或海水（或两者）混合，并在 10 天内监测种群的生化成分。标记的 RNA 比标记的 DNA 降解得更快，但两种核酸都降解到大致相同的程度（60%至 70%）。H2O 是主要的酸溶性分解产物。在孵育期间，RNA（和可能的 DNA）的降解产物被重新掺入 DNA（和可能的 RNA）中。除了代谢物回收外，无论使用砂还是海水作为接种物，在 10 天的时间内，总大分子 C 的 32%被呼吸消耗，而与核酸降解持续整个 10 天的孵育期。结果表明，死亡微生物生物量是沉积物生态系统的一种不稳定组成部分。
