scholarly journals Expanded Asgard archaea shed new light on the origin of eukaryotes and support a 2-domain tree of life

2021 ◽  
Author(s):  
Ruize Xie ◽  
Yinzhao Wang ◽  
Danyue Huang ◽  
Jialin Hou ◽  
Liuyang Li ◽  
...  
Keyword(s):  
Amino Acids ◽  
Carbon Fixation ◽  
Sister Group ◽  
Tree Of Life ◽  
Metabolic Reconstruction ◽  
Ecological Functions ◽  
Host Lineage ◽  
Phylogenomic Analyses ◽  
The Relationship ◽  
Origin Of Eukaryotes

AbstractThe hypothesis that eukaryotes originated from within the domain Archaea has been strongly supported by recent phylogenomic analyses placing Heimdallarchaeota from the Asgard superphylum as the closest known archaeal sister-group to eukaryotes. At present, only seven phyla are described in the Asgard superphylum, which limits our understanding of the relationship between eukaryotes and archaea, as well as the evolution and ecological functions of Asgard archaea. Here, we describe five novel phylum-level Asgard archaeal lineages, tentatively named Tyr-, Sigyn-, Freyr-, Hoder- and Balderarchaeota. Comprehensive phylogenomic analyses supported a new Asgard lineage Tyrarchaeota was identified as a deeper branching lineage cluster with the eukaryotic nuclear host lineage than Heimdallarchaeota that were previously considered as the closest archaeal relatives of eukaryotes. Metabolic reconstruction of Tyrarchaeota suggests a mixotrophic lifestyle of this archaea, capable of peptides and amino acids utilization while having the potential using the Wood-Ljungdahl pathway for carbon fixation and acetogenesis. This study largely expands the Asgard superphylum, provides additional evidences to support the 2-domain life tree thus sheds new light on the evolution and geochemical functions of the Asgard archaea.

scholarly journals Expanding Asgard members in the domain of Archaea shed new light on the origin of eukaryotes

2021 ◽  
Author(s):  
Ruize Xie ◽  
Yinzhao Wang ◽  
Danyue Huang ◽  
Jialin Hou ◽  
Liuyang Li ◽  
...  
Keyword(s):  
Amino Acids ◽  
Sister Group ◽  
Tree Of Life ◽  
Metabolic Reconstruction ◽  
Ecological Functions ◽  
Host Lineage ◽  
Phylogenomic Analyses ◽  
The Relationship ◽  
Origin Of Eukaryotes

AbstractThe hypothesis that eukaryotes originated from within the domain Archaea has been strongly supported by recent phylogenomic analyses placing Heimdallarchaeota from the Asgard superphylum as the closest known archaeal sister-group to eukaryotes. At present, only six phyla are described in the Asgard superphylum, which limits our understanding of the relationship between eukaryotes and archaea, as well as the evolution and ecological functions of the Asgard archaea. Here, we describe five previously unknown phylum-level Asgard archaeal lineages, tentatively named Tyr-, Sigyn-, Freyr-, Njord- and Balderarchaeota. Comprehensive phylogenomic analyses further supported the origin of eukaryotes within Archaea to form a 2-domain tree of life and a new Asgard lineage Njordarchaeota was identified as the potential closest branch with the eukaryotic nuclear host lineage rather than Heimdallarchaeota that were previously considered as the closest archaeal relatives of eukaryotes. Metabolic reconstruction of Njordarchaeota suggests a heterotrophic lifestyle, with potential capability of peptides and amino acids utilization. This study largely expands the Asgard superphylum, provides additional evidences to support the 2-domain life tree and sheds new light on the evolution of eukaryotes.

Isoleucine Plays an Important Role for Maintaining Immune Function

2019 ◽  
Vol 20 (7) ◽  
pp. 644-651 ◽  
Author(s):  
Changsong Gu ◽  
Xiangbing Mao ◽  
Daiwen Chen ◽  
Bing Yu ◽  
Qing Yang
Keyword(s):  
Amino Acids ◽  
Acid Metabolism ◽  
Branched Chain Amino Acids ◽  
Whole Body ◽  
Immune Functions ◽  
Host Defense Peptides ◽  
Innate And Adaptive Immunity ◽  
Physiological Functions ◽  
Branched Chain ◽  
The Relationship

Branched chain amino acids are the essential nutrients for humans and many animals. As functional amino acids, they play important roles in physiological functions, including immune functions. Isoleucine, as one of the branched chain amino acids, is also critical in physiological functions of the whole body, such as growth, immunity, protein metabolism, fatty acid metabolism and glucose transportation. Isoleucine can improve the immune system, including immune organs, cells and reactive substances. Recent studies have also shown that isoleucine may induce the expression of host defense peptides (i.e., β-defensins) that can regulate host innate and adaptive immunity. In addition, isoleucine administration can restore the effect of some pathogens on the health of humans and animals via increasing the expression of β-defensins. Therefore, the present review will emphatically discuss the effect of isoleucine on immunity while summarizing the relationship between branched chain amino acids and immune functions.

Study of the relationship between free amino acids and cataract in human lenses

1984 ◽  
Vol 38 (2) ◽  
pp. 177-179 ◽  
Author(s):  
B.S. Chauhan ◽  
N.C. Desai ◽  
Ramesh Bhatnagar ◽  
S.P. Garg
Keyword(s):  
Amino Acids ◽  
Free Amino Acids ◽  
Free Amino ◽  
Human Lenses ◽  
The Relationship

Origin and Early Evolution of the Eukaryotic Cell

2021 ◽  
Vol 75 (1) ◽  
Author(s):  
Toni Gabaldón
Keyword(s):  
Current Knowledge ◽  
Eukaryotic Cell ◽  
Early Evolution ◽  
Annual Review ◽  
Publication Date ◽  
Eukaryotic Evolution ◽  
Life Itself ◽  
Metabolic Interactions ◽  
Phylogenomic Analyses ◽  
Origin Of Eukaryotes

The origin of eukaryotes has been defined as the major evolutionary transition since the origin of life itself. Most hallmark traits of eukaryotes, such as their intricate intracellular organization, can be traced back to a putative common ancestor that predated the broad diversity of extant eukaryotes. However, little is known about the nature and relative order of events that occurred in the path from preexisting prokaryotes to this already sophisticated ancestor. The origin of mitochondria from the endosymbiosis of an alphaproteobacterium is one of the few robustly established events to which most hypotheses on the origin of eukaryotes are anchored, but the debate is still open regarding the time of this acquisition, the nature of the host, and the ecological and metabolic interactions between the symbiotic partners. After the acquisition of mitochondria, eukaryotes underwent a fast radiation into several major clades whose phylogenetic relationships have been largely elusive. Recent progress in the comparative analyses of a growing number of genomes is shedding light on the early events of eukaryotic evolution as well as on the root and branching patterns of the tree of eukaryotes. Here I discuss current knowledge and debates on the origin and early evolution of eukaryotes. I focus particularly on how phylogenomic analyses have challenged some of the early assumptions about eukaryotic evolution, including the widespread idea that mitochondrial symbiosis in an archaeal host was the earliest event in eukaryogenesis. Expected final online publication date for the Annual Review of Microbiology, Volume 75 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

scholarly journals Primary Research of the Relationship between Genetic Codons and Amino Acids Based on the Technology of Electronic Tongue

2021 ◽  
Vol 79 (11) ◽  
pp. 1372
Author(s):  
Zhao Zhao ◽  
Shiwen Cheng ◽  
Yuezhong Mao ◽  
Jianxi Ying ◽  
Shiyi Tian ◽  
...  
Keyword(s):  
Amino Acids ◽  
Electronic Tongue ◽  
Primary Research ◽  
The Relationship

scholarly journals Fungi of entomopathogenic potential in Chytridiomycota and Blastocladiomycota, and in fungal allies of the Oomycota and Microsporidia

IMA Fungus ◽  
2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Agata Kaczmarek ◽  
Mieczysława I. Boguś
Keyword(s):  
Biological Control Agent ◽  
Sister Group ◽  
Control Agent ◽  
Scale Insects ◽  
Black Flies ◽  
Larval Stages ◽  
Phylogenetic Studies ◽  
Lady Beetles ◽  
Molecular Phylogenetic ◽  
The Relationship

AbstractThe relationship between entomopathogenic fungi and their insect hosts is a classic example of the co-evolutionary arms race between pathogen and target host. The present review describes the entomopathogenic potential of Chytridiomycota and Blastocladiomycota fungi, and two groups of fungal allies: Oomycota and Microsporidia. The Oomycota (water moulds) are considered as a model biological control agent of mosquito larvae. Due to their shared ecological and morphological similarities, they had long been considered a part of the fungal kingdom; however, phylogenetic studies have since placed this group within the Straminipila. The Microsporidia are parasites of economically-important insects, including grasshoppers, lady beetles, bumblebees, colorado potato beetles and honeybees. They have been found to display some fungal characteristics, and phylogenetic studies suggest that they are related to fungi, either as a basal branch or sister group. The Blastocladiomycota and Chytridiomycota, named the lower fungi, historically were described together; however, molecular phylogenetic and ultrastructural research has classified them in their own phylum. They are considered parasites of ants, and of the larval stages of black flies, mosquitoes and scale insects.

3. Proteins

2021 ◽  
pp. 34-51
Author(s):  
Mark Lorch
Keyword(s):  
Amino Acids ◽  
Protein Folding ◽  
Protein Structure ◽  
Protein Structures ◽  
Structure And Function ◽  
Vast Array ◽  
A Cell ◽  
Cellular Machinery ◽  
And Function ◽  
The Relationship

This chapter examines proteins, the dominant proportion of cellular machinery, and the relationship between protein structure and function. The multitude of biological processes needed to keep cells functioning are managed in the organism or cell by a massive cohort of proteins, together known as the proteome. The twenty amino acids that make up the bulk of proteins produce the vast array of protein structures. However, amino acids alone do not provide quite enough chemical variety to complete all of the biochemical activity of a cell, so the chapter also explores post-translation modifications. It finishes by looking as some dynamic aspects of proteins, including enzyme kinetics and the protein folding problem.

NMR Studies of the Reaction of Amino Acids with Aqueous Chlorine

1997 ◽  
Author(s):  
Frank E. Scully, Jr ◽  
Barbara Conyers
Keyword(s):  
Amino Acids ◽  
Aquatic Organisms ◽  
Nondestructive Method ◽  
Resonance Spectroscopy ◽  
Nmr Studies ◽  
Wastewater Disinfection ◽  
Water And Wastewater ◽  
Gas Chromatography Mass Spectroscopy ◽  
The Relationship ◽  
By Products

Over the past 20 years, gas chromatography/mass spectroscopy (GC/MS) has been widely used to identify trace organic environmental contaminants and to study the mechanisms of the formation or transformation of organic compounds either by natural or man-made processes. In the area of water and wastewater disinfection, GC/MS has been highly successful in identifying numerous volatile organic chlorination by-products, some of which may pose undesirable health risks to humans and aquatic organisms at concentrations found in some waters. However, despite a considerable amount of research in this area much of the chemistry continues to be poorly understood. Analysis of trace organics by GC/MS relies on the assumption that the compounds to be analyzed are (1) volatile and (2) thermally stable to GC temperatures as high as 300 °C. Because nuclear magnetic resonance spectroscopy (NMR) is a mild and nondestructive method of analysis, it can reveal reactions that occur in water that cannot be observed by GC/MS. Until recently the reactions of amino acids with two or more equivalents of aqueous chlorine were believed to produce aldehydes and nitriles according to equation (1). LeCloirec and Martin have reported that the formation of nitriles in such situations may come in part from the reaction of monochloramine with aldehydes (equation (2)). Because reaction (2) may affect the distribution of products in reaction (1), it was important to determine the relationship between these two reactions. This chapter will review the applications of NMR we have used in studies of the products formed upon chlorination of amino acids.

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