Biotransformation of lignin in the ocean and its impact on marine carbon cycle

Abstract:

Microbial carbon sequestration in the ocean plays an important role in marine carbon storage to alleviate the global climate change. Lignin is the second most abundant carbon pool formed by photosynthesis on earth. The biogeochemical process in the ocean, which is mediated by heterotrophic microorganisms, is closely related to the marine carbon cycle. In recent years, the rapidly developing high-throughput sequencing technology, together with the traditional microbial technology, provides insights into the lignin-degrading microbial community, novel lignin-metabolizing microbial species, and functional genes in open environments. However, numerous studies focused on the terrestrial ecosystem, rather than marine ecosystem. The biogeochemical process of such terrestrial organic carbon in the ocean remains elusive. Therefore, analyzing the marine lignin transformation is essential in the study of marine carbon cycle. This article reviews not only the marine microbes involved in the lignin conversion, the mechanism of lignin metabolism and the links between microbial carbon metabolism and marine carbon sink, but also provides further ideas in the future.