scholarly journals Alkaliphilic Bacteria with Impact on Industrial Applications, Concepts of Early Life Forms, and Bioenergetics of ATP Synthesis

2015 ◽  
Vol 3 ◽  
Author(s):  
Laura Preiss ◽  
David B. Hicks ◽  
Shino Suzuki ◽  
Thomas Meier ◽  
Terry Ann Krulwich
Keyword(s):  
Early Life ◽  
Atp Synthesis ◽  
Life Forms ◽  
Industrial Applications ◽  
Alkaliphilic Bacteria

scholarly journals Relaxed Substrate Specificity in Qβ Replicase through Long-Term In Vitro Evolution

Life ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 32
Author(s):  
Kohtoh Yukawa ◽  
Ryo Mizuuchi ◽  
Norikazu Ichihashi
Keyword(s):  
Substrate Specificity ◽  
Early Life ◽  
Evolutionary History ◽  
Rna Replication ◽  
Life Forms ◽  
In Vitro Evolution ◽  
Present Evidence ◽  
Major Transition

A change from RNA- to DNA-based genetic systems is hypothesized as a major transition in the evolution of early life forms. One of the possible requirements for this transition is a change in the substrate specificity of the replication enzyme. It is largely unknown how such changes would have occurred during early evolutionary history. In this study, we present evidence that an RNA replication enzyme that has evolved in the absence of deoxyribonucleotide triphosphates (dNTPs) relaxes its substrate specificity and incorporates labeled dNTPs. This result implies that ancient replication enzymes, which probably evolved in the absence of dNTPs, could have incorporated dNTPs to synthesize DNA soon after dNTPs became available. The transition from RNA to DNA, therefore, might have been easier than previously thought.

The Biography of the Earth

2021 ◽  
pp. 163-180
Author(s):  
Elisabeth Ervin-Blankenheim
Keyword(s):  
Early Life ◽  
Plate Tectonics ◽  
Life Forms ◽  
Snowball Earth ◽  
The Moon ◽  
Geologic Time ◽  
Earth Systems ◽  
Organic Life ◽  
The Earth ◽  
Geologic Record

The way the planet has changed through geologic time, and life on it, the account of the Earth, is the topic of this and the next three chapters, starting in this chapter with the Precambrian Supereon. The overarching principles of geologic time, plate tectonics, and evolution worked dynamically to create the biography of the planet. This chapter traces back to the recesses of the geologic record and early Earth, from its birth and the formation of the Moon through seven-eighths of its existence, a huge span of time. Early life forms emerged during this supereon in the Archean Eon and had a profound influence on other Earth systems. Life interacted and changed the chemistry of the atmosphere through photosynthesis, so much so that the changes are thought to have sent planetary systems over an edge into multiple “Snowball Earth” episodes when most of the planet froze over. In addition to the beginning of organic life and climate, the emergence and configuration of the continents during the Precambrian are covered. Events of this supereon set the stage for the burgeoning of life forms in the next eon, the Phanerozoic.

Early Life Forms

1895 ◽  
Vol 40 (1038supp) ◽  
pp. 16596-16597
Keyword(s):  
Early Life ◽  
Life Forms

Biominerals

2005 ◽  
Vol 69 (5) ◽  
pp. 621-641 ◽  
Author(s):  
H. C. W. Skinner
Keyword(s):  
Grain Size ◽  
Calcium Phosphates ◽  
Life Forms ◽  
Industrial Applications ◽  
Chemical Characteristics ◽  
Crystal Chemical ◽  
Iron Hydroxides ◽  
Calcium Carbonates ◽  
Fine Grain ◽  
Intimate Association

AbstractBiominerals are a subset of the mineral kingdom, those created by living creatures. In spite of usually fine grain size and intimate association with organic materials, biominerals are readily identified as common mineral species. Iron hydroxides and oxyhydroxides, calcium carbonates and calcium phosphates from uni- and multi-cellular species are presented as examples of biominerals, and biomineralization processes. Their special morphological, and crystal chemical, characteristics provide unique structural contributions to the life forms that create them. Investigations of novel habitats should present opportunities to expand the number of biominerals and their potential for industrial applications.

A biota of Ediacaran aspect from lower Cambrian strata on the Digermul Peninsula, Arctic Norway

1999 ◽  
Vol 136 (6) ◽  
pp. 633-642 ◽  
Author(s):  
T. P. CRIMES ◽  
D. McILROY
Keyword(s):  
Morphological Variation ◽  
Mass Extinction ◽  
Early Life ◽  
Lower Cambrian ◽  
Life Forms ◽  
Growing Body ◽  
Extinction Event ◽  
Late Neoproterozoic ◽  
Mass Extinction Event

Three elements of the ‘Ediacara fauna’ are described from lower Cambrian strata on the Digermul Peninsula, Norway. Nimbia occlusa Fedonkin, 1980 and Tirasiana sp. occur approximately 80 m above the base of the Lower Breivik Member, which approximately coincides with the Neoproterozoic–Cambrian boundary. A specimen of Cyclomedusa sp. has also been found in the Lower Duolbasgaissa Member about 600 m above the boundary, in rocks of trilobite-bearing age.These discoveries add to a growing body of evidence that some elements of the dominantly Neoproterozoic Ediacara fauna continue into the Phanerozoic, thereby diminishing the scope of a possible late Neoproterozoic mass-extinction event.The taxa described here, particularly Nimbia and Cyclomedusa, also occur at many other localities within Neoproterozoic strata and, in common with other elements of the Ediacara fauna, display remarkable morphological variation. Some of this diversity in form is probably caused by environmental and preservational factors. The possibility that it may, at least in part, reflect an inability of these early life forms to replicate faithfully their genes during reproduction should, however, not be overlooked.

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