scholarly journals Mmp10 is required for post-translational methylation of arginine at the active site of methyl-coenzyme M reductase

2017 ◽  
Author(s):  
Zhe Lyu ◽  
Chau-wen Chou ◽  
Hao Shi ◽  
Ricky Patel ◽  
Evert C. Duin ◽  
...  

AbstractCatalyzing the key step for anaerobic methane production and oxidation, methyl-coenzyme M reductase or Mcr plays a key role in the global methane cycle. The McrA subunit possesses up to five post-translational modifications (PTM) at its active site. Bioinformatic analyses had previously suggested that methanogenesis marker protein 10 (Mmp10) could play an important role in methanogenesis. To examine its role, MMP1554, the gene encoding Mmp10 inMethanococcus maripaludis, was deleted with a new genetic tool, resulting in the specific loss of the 5-(S)-methylarginine PTM of residue 275 in the McrA subunit and a 40~60 % reduction in the maximal rates of methane formation by whole cells. Methylation was restored by complementations with the wild-type gene. However, the rates of methane formation of the complemented strains were not always restored to the wild type level. This study demonstrates the importance of Mmp10 and the methyl-Arg PTM on Mcr activity.

2017 ◽  
Vol 199 (16) ◽  
Author(s):  
Tristan Wagner ◽  
Carl-Eric Wegner ◽  
Jörg Kahnt ◽  
Ulrich Ermler ◽  
Seigo Shima

ABSTRACT The phylogenetically diverse family of methanogenic archaea universally use methyl coenzyme M reductase (MCR) for catalyzing the final methane-forming reaction step of the methanogenic energy metabolism. Some methanogens of the orders Methanobacteriales and Methanococcales contain two isoenzymes. Comprehensive phylogenetic analyses on the basis of all three subunits grouped MCRs from Methanobacteriales and Methanococcales into three distinct types: (i) MCRs from Methanobacteriales, (ii) MCRs from Methanobacteriales and Methanococcales, and (iii) MCRs from Methanococcales. The first and second types contain MCR isoenzymes I and II from Methanothermobacter marburgensis, respectively; therefore, they were designated MCR type I and type II and accordingly; the third one was designated MCR type III. For comparison with the known MCR type I and type II structures, we determined the structure of MCR type III from Methanotorris formicicus and Methanothermococcus thermolithotrophicus. As predicted, the three MCR types revealed highly similar overall structures and virtually identical active site architectures reflecting the chemically challenging mechanism of methane formation. Pronounced differences were found at the protein surface with respect to loop geometries and electrostatic properties, which also involve the entrance of the active-site funnel. In addition, the C-terminal end of the γ-subunit is prolonged by an extra helix after helix γ8 in MCR type II and type III, which is, however, differently arranged in the two MCR types. MCR types I, II, and III share most of the posttranslational modifications which appear to fine-tune the enzymatic catalysis. Interestingly, MCR type III lacks the methyl-cysteine but possesses in subunit α of M. formicicus a 6-hydroxy-tryptophan, which thus far has been found only in the α-amanitin toxin peptide but not in proteins. IMPORTANCE Methyl coenzyme M reductase (MCR) represents a prime target for the mitigation of methane releases. Phylogenetic analyses of MCRs suggested several distinct sequence clusters; those from Methanobacteriales and Methanococcales were subdivided into three types: MCR type I from Methanobacteriales, MCR type II from Methanobacteriales and Methanococcales, and the newly designated MCR type III exclusively from Methanococcales. We determined the first X-ray structures for an MCR type III. Detailed analyses revealed substantial differences between the three types only in the peripheral region. The subtle modifications identified and electrostatic profiles suggested enhanced substrate binding for MCR type III. In addition, MCR type III from Methanotorris formicicus contains 6-hydroxy-tryptophan, a new posttranslational modification that thus far has been found only in the α-amanitin toxin.


2021 ◽  
Author(s):  
Jue Wu ◽  
Shi-Lu Chen

An Ni(i) F430-like cofactor derived from vitamin B12 can catalyze methane formation in the active site of methyl-coenzyme M reductase.


FEBS Journal ◽  
2007 ◽  
Vol 274 (18) ◽  
pp. 4913-4921 ◽  
Author(s):  
Jörg Kahnt ◽  
Bärbel Buchenau ◽  
Felix Mahlert ◽  
Martin Krüger ◽  
Seigo Shima ◽  
...  

2008 ◽  
Vol 130 (33) ◽  
pp. 10907-10920 ◽  
Author(s):  
Jeffrey Harmer ◽  
Cinzia Finazzo ◽  
Rafal Piskorski ◽  
Sieglinde Ebner ◽  
Evert C. Duin ◽  
...  

2007 ◽  
Vol 129 (36) ◽  
pp. 11028-11029 ◽  
Author(s):  
Na Yang ◽  
Markus Reiher ◽  
Mi Wang ◽  
Jeffrey Harmer ◽  
Evert C. Duin

2010 ◽  
Vol 132 (2) ◽  
pp. 567-575 ◽  
Author(s):  
Sieglinde Ebner ◽  
Bernhard Jaun ◽  
Meike Goenrich ◽  
Rudolf K. Thauer ◽  
Jeffrey Harmer

2004 ◽  
Vol 186 (23) ◽  
pp. 7874-7880 ◽  
Author(s):  
Heather R. Panek ◽  
Mark R. O'Brian

ABSTRACT Bacteria are exposed to reactive oxygen species from the environment and from those generated by aerobic metabolism. Catalases are heme proteins that detoxify H2O2, and many bacteria contain more than one catalase enzyme. Also, the nonheme peroxidase alkyl hydroperoxide reductase (Ahp) is the major scavenger of endogenous H2O2 in Escherichia coli. Here, we show that aerobically grown Bradyrhizobium japonicum cells express a single catalase activity. Four genes encoding putative catalases in the B. japonicum genome were identified, including a katG homolog encoding a catalase-peroxidase. Deletion of the katG gene resulted in loss of catalase activity in cell extracts and of exogenous H2O2 consumption by whole cells. The katG strain had a severe aerobic growth phenotype but showed improved growth in the absence of O2. By contrast, a B. japonicum ahpCD mutant grew well aerobically and consumed H2O2 at wild-type rates. A heme-deficient hemA mutant expressed about one-third of the KatG activity as the wild type but grew well aerobically and scavenged low concentrations of exogenous H2O2. However, cells of the hemA strain were deficient in consumption of high concentrations of H2O2 and were very sensitive to killing by short exposure to H2O2. In addition, KatG activity did not decrease as a result of mutation of the gene encoding the transcriptional activator OxyR. We conclude that aerobic metabolism produces toxic levels of H2O2 in B. japonicum, which is detoxified primarily by KatG. Furthermore, the katG level sufficient for detoxification does not require OxyR.


2000 ◽  
Vol 275 (6) ◽  
pp. 3755-3760 ◽  
Author(s):  
Thorsten Selmer ◽  
Jörg Kahnt ◽  
Marcel Goubeaud ◽  
Seigo Shima ◽  
Wolfgang Grabarse ◽  
...  

2017 ◽  
Author(s):  
Dipti D. Nayak ◽  
Nilkamal Mahanta ◽  
Douglas A. Mitchell ◽  
William W. Metcalf

AbstractThe enzyme methyl-coenzyme M reductase (MCR), found in strictly anaerobic methanogenic and methanotrophic archaea, catalyzes a reversible reaction involved in the production and consumption of the potent greenhouse gas methane. The α subunit of this enzyme (McrA) contains several unusual post-translational modifications, including an exceptionally rare thioamidation of glycine. Based on the presumed function of homologous genes involved in the biosynthesis of thioamide-containing natural products, we hypothesized that the archaealtfuAandycaOgenes would be responsible for post-translational installation of thioglycine into McrA. Mass spectrometric characterization of McrA in a ΔycaO-tfuAmutant of the methanogenic archaeonMethanosarcina acetivoransrevealed the presence of glycine, rather than thioglycine, supporting this hypothesis. Physiological characterization of this mutant suggested a new role for the thioglycine modification in enhancing protein stability, as opposed to playing a direct catalytic role. The universal conservation of this modification suggests that MCR arose in a thermophilic ancestor.


2016 ◽  
Vol 128 (36) ◽  
pp. 10788-10791 ◽  
Author(s):  
Tristan Wagner ◽  
Jörg Kahnt ◽  
Ulrich Ermler ◽  
Seigo Shima

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