Protein Signatures Distinctive of Alpha Proteobacteria and Its Subgroups and a Model for α –Proteobacterial Evolution

  title={Protein Signatures Distinctive of Alpha Proteobacteria and Its Subgroups and a Model for $\alpha$ –Proteobacterial Evolution},
  author={Radhey S. Gupta},
  journal={Critical Reviews in Microbiology},
  pages={101 - 135}
  • Radhey S. Gupta
  • Published 1 January 2005
  • Biology
  • Critical Reviews in Microbiology
Alpha (α) proteobacteria comprise a large and metabolically diverse group. No biochemical or molecular feature is presently known that can distinguish these bacteria from other groups. The evolutionary relationships among this group, which includes numerous pathogens and agriculturally important microbes, are also not understood. Shared conserved inserts and deletions (i.e., indels or signatures) in molecular sequences provide a powerful means for identification of different groups in clear… 

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Molecular signatures in protein sequences that are characteristics of the phylum Aquificae.

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A new alpha-proteobacterial clade of Bdellovibrio-like predators: implications for the mitochondrial endosymbiotic theory.

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The phylogeny of proteobacteria: relationships to other eubacterial phyla and eukaryotes.

  • R. Gupta
  • Biology
    FEMS microbiology reviews
  • 2000
An unexpected but important aspect of the relationship deduced here is that the main eubacterial phyla are related to each other linearly rather than in a tree-like manner, suggesting that the major evolutionary changes within Bacteria have taken place in a directional manner.

Protein Phylogenies and Signature Sequences: A Reappraisal of Evolutionary Relationships among Archaebacteria, Eubacteria, and Eukaryotes

Evidence from indels supports the view that the archaebacteria probably evolved from gram-positive bacteria and suggests that this evolution occurred in response to antibiotic selection pressures, and an alternative model of microbial evolution based on the use of indels of conserved proteins and the morphological features of prokaryotic organisms is proposed.

Signature sequences in diverse proteins provide evidence for the late divergence of the Order Aquificales.

  • E. GriffithsRadhey S. Gupta
  • Biology, Environmental Science
    International microbiology : the official journal of the Spanish Society for Microbiology
  • 2004
The results provide strong and consistent evidence that the Aquificales diverged after the branching of Firmicutes, Actinob bacteria, Thermotoga, Deinococcus-Thermus, green nonsulfur bacteria, Cyanobacteria, Spirochetes, Chlamydiae, and CFBG group, but before the emergence of the Proteobacteria.

The Phylogeny and Signature Sequences Characteristics of Fibrobacteres, Chlorobi, and Bacteroidetes

Signatures in a number of other proteins provide evidence that the FCB group of bacteria diverged at a similar time as the Chlamydiae group, and that the Spirochetes and Aquificales groups are its closest relatives.

Distinctive Protein Signatures Provide Molecular Markers and Evidence for the Monophyletic Nature of the Deinococcus-Thermus Phylum

The presence of these signatures in various species from all three known genera within this phylum, viz., Deinococcus, Thermus, and Meiothermus, provide evidence that they are likely distinctive characteristics of the entire phylum which were introduced in a common ancestor of this group.

Evolutionary relationships among eubacterial groups as inferred from GroEL (chaperonin) sequence comparisons.

The general observations suggest that GroEL proteins provide valuable evolutionary tools for defining evolutionary relationships among the eubacterial lineage of life.

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  • Biology
    Journal of Molecular Evolution
  • 2004
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Evolutionary relationships among photosynthetic bacteria

All main groups within bacteria can now be defined in clear molecular terms and their relative branching orders logically deduced using the indel model.

Critical issues in bacterial phylogeny.

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Protein signatures distinctive of chlamydial species: horizontal transfers of cell wall biosynthesis genes glmU from archaea to chlamydiae and murA between chlamydiae and Streptomyces.

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