Iron-Only and Vanadium Nitrogenases: Fail-Safe Enzymes or Something More?

Iron-Only and Vanadium Nitrogenases: Fail-Safe Enzymes or Something More? Annu Rev Microbiol. 2020 Jul 13;: Authors: Harwood CS Abstract The enzyme molybdenum nitrogenase converts atmospheric nitrogen gas to ammonia and is of critical importance for the cycling of nitrogen in the biosphere and for the sustainability of life. Alternative vanadium and iron-only nitrogenases that are homologous to molybdenum nitrogenases are also found in archaea and bacteria, but they have a different transition metal, either vanadium or iron, at their active sites. So far alternative nitrogenases have only been found in microbes that also have molybdenum nitrogenase. They are less widespread than molybdenum nitrogenase in bacteria and archaea, and they are less efficient. The presumption has been that alternative nitrogenases are fail-safe enzymes that are used in situations where molybdenum is limiting. Recent work indicates that vanadium nitrogenase may play a role in the global biological nitrogen cycle and iron-only nitrogenase may contribute products that shape microbial community interactions in nature. Expected final online publication date for the Annual Review of Microbiology, Volume 74 is September 8, 2020. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates. PMID: 32660386 [PubMed - as supplied by publisher]
Source: Annual Review of Microbiology - Category: Microbiology Authors: Tags: Annu Rev Microbiol Source Type: research