Methylacidiphilum fumariolicum

From MicrobeWiki, the student-edited microbiology resource

Classification


Methylacidiphilum fumariolicum


Domain: Bacteria

Phylum: Verrucomicrobia

Class:

Order: Methylacidiphilales

Family: Methylacidiphilaceae

Genus: Methylacidiphilum

Species: Methylacidiphilum fumariolicum

Description and Significance

Methylacidiphilum fumariolicum is an extremely acidophilic methanotrophic microbe first discovered in 2007 in volcanic pools near Naples, Italy by Huub Op den Camp and other scientists. This microbe endures very hot temperatures (50-60 C) and mud that is extremely acidic (pH 2-5). After studying the mudpot in which the microbe lived, it was found that M. fumariolicum is strictly dependent on the presence of rare earth metals such as lanthanides. It is theorized that lanthanides provide superior catalytic properties to a key enzyme for both methanotrophs and methylotrophs. When the bacteria’s enzyme methanol dehydrogenase was analyzed, scientist found traces of whichever rare earth element that they had added, indicating storing of the elements by the enzyme. [1]

Genome Structure

Genome Details [2] :

The genome of Methylacidiphilum fumariolicum is 2.36 Mbp in size.

GC content = 40.9%

2,283 protein encoding genes

Biosynthetic pathways and tRNAs for all 20 amino acids were present

Metabolism

Energy

Methylacidiphilum fumariolicum obtain their energy through the oxidation of methane in anaerobic conditions. Rare earth metals, such as lanthanum (Ln), cerium (Ce), praseodymium (Pr) and neodymium (Nd), are essential co-factors for the enzyme methanol dehydrogenase, which is used to metabolize the methanol produced from the oxidation of methane. [1]

Carbon Fixation

Methylacidiphilum fumariolicum has been found to be an autotroph. Its main carbon source is CO2 and is fixed via the Calvin-Benson cycle. Studies have shown that no growth in a Methylacidiphilum fumariolicum colony is seen when CO2 concentrations are less than 0.3% (v/v). Further verification of Methylacidiphilum fumariolicum means of CO2 fixation was seen in a genome analysis. All the genes required for Calvin-Benson cycle were transcribed. [4]

Nitrogen Fixation

Methylacidiphilum fumariolicum has been found to fix nitrogen at low oxygen concentrations (less than 2% v/v) in chemostat cultures based on the following equation:

Nitrogen Fixation Equation.png

The optimal oxygen concentration for Methylacidiphilum fumariolicum nitorgen fixation is 0.5% v/v. Studies show that this species poses the essential genes for nitrogen fixation (The genes encoding the structural protein (nifH, nifD and nifK) and the genes encoding cofactor biosynthesis (nifE,nifN and nifX)). Methylacidiphilum fumariolicum was also found to be more oxygen sensitive than most other proteobacterial methanotrophs. This could be due to the fact that during nitrogen fixation there was found to be nitrogenase activity, which is known to be oxygen sensitive. [3]

Ecology

References

[1] Pol, A., T. Barends, A. Dietl, A. Khadem, J. Eygensteyn, M. Jetten, and H. Op den Camp. "Rare Earth Metals Are Essential for Methanotrophic Life in Volcanic Mudpots." Environmental Microbiology (2013): N/a. Print.

[2] Khadem, A., A. Wieczorek, A. Pol, S. Vuilleumier, H. Harhangi, P. Dunfield, M. Kalyuzhnaya, J. Murrell, K. Francoijs, H. Stunnenberg, L. Stein, A. Dispirito, J. Semrau, A. Lajus, C. Medigue, M. Klotz, M. Jetten, and H. Op Den Camp. "Draft Genome Sequence of the Volcano-Inhabiting Thermoacidophilic Methanotroph Methylacidiphilum Fumariolicum Strain SolV." Journal of Bacteriology 194.14 (2012): 3729-730. Print.

[3] Khadem, A. F., A. Pol, M. S. M. Jetten, and H. J. M. Op Den Camp. "Nitrogen Fixation by the Verrucomicrobial Methanotroph 'Methylacidiphilum Fumariolicum' SolV."Microbiology 156.4 (2010): 1052-059. Print.

[4] Khadem, A. F., A. Pol, A. Wieczorek, S. S. Mohammadi, K.-J. Francoijs, H. G. Stunnenberg, M. S. M. Jetten, and H. J. M. Op Den Camp. "Autotrophic Methanotrophy in Verrucomicrobia: Methylacidiphilum FumariolicumSolV Uses the Calvin-Benson-Bassham Cycle for Carbon Dioxide Fixation." Journal of Bacteriology 193.17 (2011): 4438-446. Print.

Edited by Keely Chandler and Kelsey Sharples, students of Drs. Kaz Kashefi Edward Walker for MMG 425 at Michigan State University, 2014.