gram-negative eubacteria, gram-positive eubacteria and archaebacteria (Barton
1995).
In the 1990s of the last century, advances in molecular biology and DNA
technology, as well as the classification of organisms proposed by Woese, based
on ribosomal gen analysis, had a great impact on the traditional classification,
particularly of microorganisms (Woese et al. 1990). The phylogenetic analysis
based on the comparative analysis of the sequences of the 16S rRNA gene
establishes phylogenetic relationships among microorganisms up to a genus and
species approach. Therefore, the importance generated around SRB and with the
development of rRNA phylogenetic analysis gave a great step for the taxonomy and
phylogeny of the sulfate-reducing prokaryotes. The phylogenetic analysis of the 16S
rRNA gene showed that the sulfate- reducing prokaryotes are divided into four
phylogenetic lineages: mesophilic Gram-negative SRB, Gram-positive sporeforming SRB, thermophilic sulfate-reducing archaea (SRA) and SRB (Castro et al.
2000). Gram-negative SRB are located in the Deltaproteobacteria subdivision,
where there are other non-sulfate-reducing bacteria, but within this division, there
are two relevant families of SRB: Desulfovibrionaceae and Desulfobacteriaceae. The
family Desulfovibrionaceae is basically constituted by species of the genus
Desulfovibrio (Voordouw 1995). The main genera of the family Desulfobacteriaceae
are
Desulfobacter,
Desulfococcus,
Desulfobulbus,
Desulfobacterium,
Desulfosarcina, Desulfoneum and Desulfotulus, among others. The genus
Desulfotomaculum is the most representative of Gram-positive SRB, and their
species form spores. The thermophilic reducing sulfate prokaryotes are divided
into bacterial and archaea species (Castro et al. 2000).
In the first decade of this century, Muyzer and Stams reported that due to the
discovery and isolation of new species (Muyzer and Stams 2008) and the increasing
of the number of 16S rRNA gene sequences reported in the Genebank, this group of
microorganisms is divided in seven phylogenetic lineages: five within the Bacteria
and two within the Archaea. Most SRB belong to the class Deltaproteobacteria with
approximately 23 genera, and the Gram-positive bacteria within the Clostridia,
followed
by
lineages
Nitrospirae
(genus
Thermodesulfovibrio),
Thermodesulfobacteria and Thermodesulfobiaceae (only thermophilic sulfate
reducers). The lineages to SRA belong to genus Archaeoglobus in the Euryarchaeota
and the genera Thermocladium and Caldivirga in the Crenarchaeota.
In the next decades up to today, using of molecular technique and functional
markers as dsr or asr, functional genes that codify dissimilatory sulfite reductase and
anaerobic sulfite reductase, respectively, has increased the knowledge of novel
sulfate/sulfite-reducing microorganisms (Jiang et al. 2009; Meyer and Kuever
2007; Wagner et al. 2005). In parallel, different studies revealed the capacity sulfate
or sulfite-reducing in at least 13 additional bacterial and archaeal lineages, which at
the moment were not associated with the metabolism dissimilatory of sulfate or
sulfite. These include the phyla Acidobacteria, Planctomycetes, Verrucomicrobia
and Armatimonadetes, among others. Besides, 8 of these 13 are candidate phyla
without isolated representatives, which only represent uncultured microorganisms
(Müller et al. 2015; Wörner and Pester 2019).
376
M. I. Neria-González and R. Aguilar-López
1995).
In the 1990s of the last century, advances in molecular biology and DNA
technology, as well as the classification of organisms proposed by Woese, based
on ribosomal gen analysis, had a great impact on the traditional classification,
particularly of microorganisms (Woese et al. 1990). The phylogenetic analysis
based on the comparative analysis of the sequences of the 16S rRNA gene
establishes phylogenetic relationships among microorganisms up to a genus and
species approach. Therefore, the importance generated around SRB and with the
development of rRNA phylogenetic analysis gave a great step for the taxonomy and
phylogeny of the sulfate-reducing prokaryotes. The phylogenetic analysis of the 16S
rRNA gene showed that the sulfate- reducing prokaryotes are divided into four
phylogenetic lineages: mesophilic Gram-negative SRB, Gram-positive sporeforming SRB, thermophilic sulfate-reducing archaea (SRA) and SRB (Castro et al.
2000). Gram-negative SRB are located in the Deltaproteobacteria subdivision,
where there are other non-sulfate-reducing bacteria, but within this division, there
are two relevant families of SRB: Desulfovibrionaceae and Desulfobacteriaceae. The
family Desulfovibrionaceae is basically constituted by species of the genus
Desulfovibrio (Voordouw 1995). The main genera of the family Desulfobacteriaceae
are
Desulfobacter,
Desulfococcus,
Desulfobulbus,
Desulfobacterium,
Desulfosarcina, Desulfoneum and Desulfotulus, among others. The genus
Desulfotomaculum is the most representative of Gram-positive SRB, and their
species form spores. The thermophilic reducing sulfate prokaryotes are divided
into bacterial and archaea species (Castro et al. 2000).
In the first decade of this century, Muyzer and Stams reported that due to the
discovery and isolation of new species (Muyzer and Stams 2008) and the increasing
of the number of 16S rRNA gene sequences reported in the Genebank, this group of
microorganisms is divided in seven phylogenetic lineages: five within the Bacteria
and two within the Archaea. Most SRB belong to the class Deltaproteobacteria with
approximately 23 genera, and the Gram-positive bacteria within the Clostridia,
followed
by
lineages
Nitrospirae
(genus
Thermodesulfovibrio),
Thermodesulfobacteria and Thermodesulfobiaceae (only thermophilic sulfate
reducers). The lineages to SRA belong to genus Archaeoglobus in the Euryarchaeota
and the genera Thermocladium and Caldivirga in the Crenarchaeota.
In the next decades up to today, using of molecular technique and functional
markers as dsr or asr, functional genes that codify dissimilatory sulfite reductase and
anaerobic sulfite reductase, respectively, has increased the knowledge of novel
sulfate/sulfite-reducing microorganisms (Jiang et al. 2009; Meyer and Kuever
2007; Wagner et al. 2005). In parallel, different studies revealed the capacity sulfate
or sulfite-reducing in at least 13 additional bacterial and archaeal lineages, which at
the moment were not associated with the metabolism dissimilatory of sulfate or
sulfite. These include the phyla Acidobacteria, Planctomycetes, Verrucomicrobia
and Armatimonadetes, among others. Besides, 8 of these 13 are candidate phyla
without isolated representatives, which only represent uncultured microorganisms
(Müller et al. 2015; Wörner and Pester 2019).
376
M. I. Neria-González and R. Aguilar-López