title: The mcrA gene as an alternative to 16S rRNA in the phylogenetic analysis of methanogen populations in landfill.
abstract: Inferred amino acid sequences of the methyl coenzyme-M reductase (mcrA) gene from five different methanogen species were aligned and two regions with a high degree of homology flanking a more variable region were identified. Analysis of the DNA sequences from the conserved regions yielded two degenerate sequences from which a forward primer, a 32-mer, and a reverse primer, a 23-mer, could be derived for use in the specific PCR-based detection of methanogens. The primers were successfully evaluated against 23 species of methanogen representing all five recognized orders of this group of Archaea, generating a PCR product between 464 and 491 bp. Comparisons between the mcrA and 16S small subunit rRNA gene sequences using PHYLIP demonstrated that the tree topologies were strikingly similar. Methods were developed to enable the analysis of methanogen populations in landfill using the mcrA gene as the target. Two landfill sites were examined and 63 clones from a site in Mucking, Essex, and 102 from a site in Odcombe, Somerset, were analysed. Analysis revealed a far greater diversity in the methanogen population within landfill material than has been seen previously.
authors.affiliation: Centre for Applied Microbiology and Research, Porton Down, Salisbury, Wiltshire SP4 0JG, UK1.
authors.forename: Philip E
authors.initials: PE
authors.lastname: Luton
authors.affiliation: Centre for Applied Microbiology and Research, Porton Down, Salisbury, Wiltshire SP4 0JG, UK1.
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Wayne
authors.affiliation: Centre for Applied Microbiology and Research, Porton Down, Salisbury, Wiltshire SP4 0JG, UK1.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Sharp
authors.affiliation: Centre for Applied Microbiology and Research, Porton Down, Salisbury, Wiltshire SP4 0JG, UK1.
authors.forename: Paul W
authors.initials: PW
authors.lastname: Riley
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D019641:DNA, Archaeal / Q000032:analysis; D019605:Euryarchaeota / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D008969:Molecular Sequence Data; D010088:Oxidoreductases; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000032:analysis* / Q000235:genetics; D015183:Restriction Mapping / Q000379:methods
chemical_list: D001426:Bacterial Proteins; D019641:DNA, Archaeal; D012336:RNA, Ribosomal, 16S; D010088:Oxidoreductases; C088145:mcrA protein, Streptomyces lavendulae