Table of Contents Author Guidelines Submit a Manuscript
Archaea
Volume 2017 (2017), Article ID 7046026, 12 pages
https://doi.org/10.1155/2017/7046026
Research Article

A Flexible System for Cultivation of Methanococcus and Other Formate-Utilizing Methanogens

Department of Microbiology, University of Georgia, Athens, GA 30602-2605, USA

Correspondence should be addressed to William B. Whitman

Received 22 June 2017; Accepted 24 August 2017; Published 19 November 2017

Academic Editor: William W. Metcalf

Copyright © 2017 Feng Long et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Many hydrogenotrophic methanogens use either H2 or formate as the major electron donor to reduce CO2 for methane production. The conventional cultivation of these organisms uses H2 and CO2 as the substrate with frequent replenishment of gas during growth. H2 is explosive and requires an expensive gassing system to handle safely. Formate is as an ideal alternative substrate from the standpoints of both economy and safety but leads to large changes in the culture pH during growth. Here, we report that glycylglycine is an inexpensive and nontoxic buffer suitable for growth of Methanococcus maripaludis and Methanothermococcus okinawensis. This cultivation system is suitable for growth on liquid as well as solid medium in serum bottles. Moreover, it allows cultivation of liter scale cultures without expensive fermentation equipment. This formate cultivation system provides an inexpensive and flexible alternative for the growth of formate-utilizing, hydrogenotrophic methanogens.