Framework : Prokaryotic Cell Evolution

I speculate that ProCells arose on Inner Ort comets, minor planets, Theia and ProtoEarth . They transformed into Precells after impacts of a Titan-like Theia and hydrophobic Late Heavy Bombardment Worlds. The physiochemistry of Hadean Earth allowed Precells to evolve into Prokaryocytes (Archaea followed by Eubacteria). Subsequent symbioses of Prokaryocytes and Viruses created Eukaryocytes .

The Archaea evolved from Methane producing Eocytes while Eubacteria evolved from Acetate producing Korarchaea. Lipid membranes changed due to evolution in different redox, temperature, hydrophobic, and Cobalt concentration environments. However, transcription, translation , and the genetic code have a common inheritance.

The first Eubacteria were Acetothermus like cells that evolved from Archaic Thermoplasmatales. Carbon Monoxide, Carbon Dioxide, and Hydrogen based autotrophy was their earliest means of growth. The Autotrophs diversified into various electron donor and acceptor types (chemo-inorganic/litho, chemo-organic, and phototrophic). Subsequently, Heterotrophs evolved from Chemo-organic Autotrophs and created predation based ecosystems. Predation resulted in symbiotic events marked by turning points in evolution. ( Such as monoderm to diderm transitions, evolution of cyanobacteria, and viral endosymbiotic events.) Archaic Heterotrophs subsequently evolved into Proterozoic Autotrophs through DNA transpositions and secondary/ tertiary symbiotic events.

.Prokaryotic evolution was impacted by bacteriophage based elements and prokaryote-prokaryote symbioses. Mobile genetic elements were responsible for the origin and evolution of higher complexity. Natural Selection from temperature, humidity, and radiation fluctuations interacted with mobile genetic element based radiations to evolve new elements and prokaryotic cells.

The Archaic time period of prokaryotic evolution was marked by dramatic changes in the Methane, Sulfur-Sulfide-Sulfate, Oxygen, Carbon Monoxide-Dioxide, Nitrogen-Nitrate, and Metal (Mn, Zn, Fe, Co, Cu, Ca, Mg, Mo, Strontium, Tungsten, Ag, Au, Hg ) levels of the atmosphere and oceans. A model of prokaryotic evolution is needed that matches the earth's mineral and gas historic patterns with the Microbiome's of those periods. Such a model can be constructed by looking at metabolic operons and their evolutionary presence. The horizontal transfer of these operons is mediated by viral elements and potentially delivered from cosmic sources.

Most Recent Model based on multiple genes:

Cellular life forms are like Matryoshka/Babushka Dolls that show the history of our earliest ancestors in the center and novel life forms in the periphery. The history of the conversion of free living life forms to free living parasites, symbionts, and agents of genetic change shows a helical evolutionary pattern. The mobile genetic elements show a Mirror in Mirror display of newer genetic elements nesting in the center of older genetic elements . This nesting phenomenon is exemplified by insertion sequences in archaea and the insertion history of DNA transposons. The encapsulation processes work in tandem with the integration processes to evolve life. Analysis of twintrons, symbioses, and other forms of nesting will help unravel the amazing pathways of evolution.

What cellular life form developed first on Earth?

1. Archaea/Eocytes arose before Eubacteria

Support for this scenario can be seen in the evolution of the Nif H gene in archaeic bacteria followed by monodermal and then didermal eubacteria. See (Expression and Association of Group IV Nitrogenase NifD and NifH Homologs in the Non-Nitrogen-Fixing Archaeon Methanocaldococcus jannaschii and Origin and Spread of Bacteriochlorophyll Biosynthesis Proteins. ) "The evolutionary history of protein fold families and proteomes confirms that the archaeal ancestor is more ancient than the ancestors of other superkingdoms . "


2. Archaea and Eubacteria evolved separately and at the same time.

Forterre proposes that viral infection events created 3 separate superkingdoms and thus there is no monophyly of all cellular life forms. (see Three RNA cells for ribosomal lineages and three DNA viruses to replicate their genomes: a hypothesis for the origin of cellular domain)

3. Archaea are derived from Eubacteria .

Cavalier Smith proposes that Chlorobacteria form the root of the prokaryote tree and archaea are derived from Actinobacteria.

Lake proposes a circular tree root between firmicutes and actinobacterial ancestors. He suggests that archaea are derived from the Firmicutes.

Valas and Bourne propose that Archaea are derived from Neomura which arose from Firmicutes/Clostridia due to a DNA virus infection

A refined understanding of origin requires separating the phylogenetic history of transcriptional, translational, replicative, metabolic. and structural genes of early life forms. The answer to the question "Which genes arose first ?" provides better insights into the evolution of cells within the framework of the Public Goods Hypothesis.

Forterre suggests that eubacteria, archaea, and eukaryotic DNA replication arose from independent viral infection of pre-archaeal ribosome containing cells (chronocytes). Similarly, my working model suggests that Eocytes developed the first replicative metabolic systems with stable membranes. These Eocytes evolved into archaea and were later transformed by viral infections and other symbiotic processes into the Eubacterial and Eukayotic lineages. I speculate that symbiotic forms of Eocytes and Pre LECA cells evolved into bacteriophages, virophages, and NCLD viruses. ( see 4th NCLDV viral domain of dna replication proteins rooted between the archaea and eukaryota and Phylogenetic and Phyletic Studies of Informational Genes in Genomes Highlight Existence of a 4th Domain of Life Including Giant Viruses)

Did monoderm prokaryotes evolve into diderms or vice versa ?

Current data supports a model of monoderms evolving into non-LPS diderms followed by diderms with LPS. see (Origin of diderm (Gram-negative) bacteria: antibiotic selection pressure rather than endosymbiosis likely led to the evolution of bacterial cells with two membranes ) There is also evidence that a branch of monodermic actinobacteria independently evolved into didermal corynebacteria with mycolic acids in their outer membrane. Furthermore, the Negativicutes order from gram positive clostridia related firmicutes appears to have independently evolved a didermal membrane.

Another possibility is that anoxygenic photosynthetic halobacteria sporolated in the presence of a diderm promoting plasmid. The resulting proto endospore became the first diderm during the Hadean Epoch. The primordial diderm was a LPS negative, didermal deinococcus-thermus organism. These hadobacteria then evolved into LPS positive cyanobacteria as proposed by Cavalier Smith. Multiple horizontal gene transfers where involved in the transition from anoxygenic monodermal photosynthesis to didermal oxygenic photosynthesis during the Archaen Epoch.

Alternatively, photosensitive nanohaloarchaea evolved into photosynthesizing heliobacteria followed by an endosymbiosis with actinobacteria to create cyanobacteria. Similar archaea + gram positive eubacterial symbioses/lateral gene transfers or gram positive + gram positive symbioses gave rise to the separate gram negative bacteria families. (such as proteobacteria, spirochaetes, FCB group, and PVC super group )

How did mobile genetic elements effect the origin and evolution of prokaryotes?

How did the physiochemistry of our Solar System, atmosphere , hydrosphere, and crust evolve life ?

What is the origin and evolution of prokaryotic vesicles ?

Phylogenetic Trees , Species Trees, Taxonomy Browser of Euryarchaea and Eubacteria


Proc Natl Acad Sci U S A. 2012 Dec 11;109(50):20537-42. Epub 2012 Nov 26.
Acquisition of 1,000 eubacterial genes physiologically transformed a methanogen at the origin of Haloarchaea.
Nelson-Sathi S, Dagan T, Landan G, Janssen A, Steel M, McInerney JO, Deppenmeier U, Martin WF.

Narasingarao, Priya , Podell, Sheila, Ugalde, Juan A, Brochier-Armanet, Celine, Emerson, Joanne B, Brocks, Jochen J , Heidelberg, Karla B , Banfield, Jillian F , Allen, Eric E
De novo metagenomic assembly reveals abundant novel major lineage of Archaea in hypersaline microbial communities International Society for Microbial Ecology ISME J 2012/01

Rohit Ghai, Lejla Pašic, Ana Beatriz Fernández, Ana-Belen Martin-Cuadrado, Carolina Megumi Mizuno, Katherine D. McMahon, R. Thane Papke, Ramunas Stepanauskas, Beltran Rodriguez-Brito, Forest Rohwer, Cristina Sánchez-Porro, Antonio Ventosa & Francisco Rodríguez-Valera New Abundant Microbial Groups in Aquatic Hypersaline Environments Scientific Reports 1, Article number: 135 Received 22 August 2011 Accepted 10 October 2011 Published 31 October 2011

Genomic Analysis of Deeply Branching Thermophile Provides Clues to Early Life on Earth

An Ancient Pathway Combining Carbon Dioxide Fixation with the Generation and Utilization of a Sodium Ion Gradient for ATP Synthesis

Autotrophic Carbon Fixation in Archaea

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