N2O-producing microorganisms in the gut of the earthworm Aporrectodea caliginosa are indicative of ingested soil bacteria.

ABSTRACT: The main objectives of this study were (i) to determine if gut wall-associated microorganisms are responsible for the capacity of earthworms to emit nitrous oxide (N(2)O) and (ii) to characterize the N(2)O-producing bacteria of the earthworm gut. The production of N(2)O in the gut of garden soil earthworms (Aporrectodea caliginosa) was mostly associated with the gut contents rather than the gut wall. Under anoxic conditions, nitrite and N(2)O were transient products when supplemental nitrate was reduced to N(2) by gut content homogenates. In contrast, nitrite and N(2)O were essentially not produced by nitrate-supplemented soil homogenates. The most probable numbers of fermentative anaerobes and microbes that used nitrate as a terminal electron acceptor were approximately 2 orders of magnit

SUBMITTER: Ihssen J 

PROVIDER: S-EPMC150113 | biostudies-literature | 2003 Mar

REPOSITORIES: biostudies-literature