scholarly journals Protein Receptors Evolved from Homologous Cohesion Modules That Self-Associated and Are Encoded by Interactive Networked Genes

Life ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1335
Author(s):  
Donard S. Dwyer
Keyword(s):  
Sequence Similarity ◽  
Building Blocks ◽  
Amino Acid Sequence Similarity ◽  
Homologous Proteins ◽  
Structural Domains ◽  
Evolutionary Origins ◽  
Protein Receptors ◽  
Chromatin Structural ◽  
Binding Peptides ◽  
Self Association

Previously, it was proposed that protein receptors evolved from self-binding peptides that were encoded by self-interacting gene segments (inverted repeats) widely dispersed in the genome. In addition, self-association of the peptides was thought to be mediated by regions of amino acid sequence similarity. To extend these ideas, special features of receptors have been explored, such as their degree of homology to other proteins, and the arrangement of their genes for clues about their evolutionary origins and dynamics in the genome. As predicted, BLASTP searches for homologous proteins detected a greater number of unique hits for queries with receptor sequences than for sequences of randomly-selected, non-receptor proteins. This suggested that the building blocks (cohesion modules) for receptors were duplicated, dispersed, and maintained in the genome, due to structure/function relationships discussed here. Furthermore, the genes coding for a representative panel of receptors participated in a larger number of gene–gene interactions than for randomly-selected genes. This could conceivably reflect a greater evolutionary conservation of the receptor genes, with their more extensive integration into networks along with inherent properties of the genes themselves. In support of the latter possibility, some receptor genes were located in active areas of adaptive gene relocation/amalgamation to form functional blocks of related genes. It is suggested that adaptive relocation might allow for their joint regulation by common promoters and enhancers, and affect local chromatin structural domains to facilitate or repress gene expression. Speculation is included about the nature of the coordinated communication between receptors and the genes that encode them.

Overproduction and domain structure of the glutamyl-tRNA synthetase of Escherichia coli

1989 ◽  
Vol 67 (8) ◽  
pp. 404-410 ◽  
Author(s):  
Anne Brisson ◽  
Yves V. Brun ◽  
Alexander W. Bell ◽  
Paul H. Roy ◽  
Jacques Lapointe
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Amino Acid Sequence ◽  
Domain Structure ◽  
Sequence Similarity ◽  
Trna Synthetase ◽  
Amino Acid Sequence Similarity ◽  
Structural Domains ◽  
E Coli ◽  
Domain Structures

The charging of glutamate on tRNAGlu is catalyzed by glutamyl-tRNA synthetase, a monomer of 53.8 kilodaltons in Escherichia coli. To obtain the large amounts of enzyme necessary for the identification of structural domains, we have inserted the structural gene gltX in the conditional runaway-replication plasmid pOU61, which led to a 350-fold overproduction of glutamyl-tRNA synthetase. Partial proteolysis of this enzyme revealed the existence of preferential sites of attack that, according to their N-terminal sequences, delimit regions of 12.9, 2.3, 12.1, and 26.5 kilodaltons from the N- to C-terminal of the enzyme. Their sizes suggest that the 2.3-kilodalton fragment is a hinge structure, and that those of 12.9, 12.1, and 26.5 kilodaltons are domain structures. The 12.9-kilodalton domain of the glutamyl-tRNA synthetase of E. coli is the only long region of this enzyme displaying a good amino acid sequence similarity with the glutaminyl-tRNA synthetase of Escherichia coli.Key words: glutamyl-tRNA synthetase, structural domains, overproduction, runaway-replication plasmid, Escherichia coli.

scholarly journals Overexpression of the pitaya phosphoethanolamine N-methyltransferase gene (HpPEAMT) enhanced simulated drought stress in tobacco

2021 ◽  
Author(s):  
Ai-Hua Wang ◽  
Lan Yang ◽  
Xin-Zhuan Yao ◽  
Xiao-Peng Wen
Keyword(s):  
Drought Stress ◽  
Stress Response ◽  
Transgenic Plants ◽  
Drought Tolerance ◽  
Transgenic Tobacco ◽  
Sequence Similarity ◽  
Amino Acid Sequence Similarity ◽  
Transgenic Tobacco Plants ◽  
Wild Type ◽  
Tobacco Plants

AbstractPhosphoethanolamine N-methyltransferase (PEAMTase) catalyzes the methylation of phosphoethanolamine to produce phosphocholine and plays an important role in the abiotic stress response. Although the PEAMT genes has been isolated from many species other than pitaya, its role in the drought stress response has not yet been fully elucidated. In the present study, we isolated a 1485 bp cDNA fragment of HpPEAMT from pitaya (Hylocereus polyrhizus). Phylogenetic analysis showed that, during its evolution, HpPEAMT has shown a high degree of amino acid sequence similarity with the orthologous genes in Chenopodiaceae species. To further investigate the function of HpPEAMT, we generated transgenic tobacco plants overexpressing HpPEAMT, and the transgenic plants accumulated significantly more glycine betaine (GB) than did the wild type (WT). Drought tolerance trials indicated that, compared with those of the wild-type (WT) plants, the roots of the transgenic plants showed higher drought tolerance ability and exhibited improved drought tolerance. Further analysis revealed that overexpression of HpPEAM in Nicotiana tabacum resulted in upregulation of transcript levels of GB biosynthesis-related genes (NiBADH, NiCMO and NiSDC) in the leaves. Furthermore, compared with the wild-type plants, the transgenic tobacco plants displayed a significantly lower malondialdehyde (MDA) accumulation and higher activities of the superoxide dismutase (SOD) and peroxidase (POD) antioxidant enzymes under drought stress. Taken together, our results suggested that HpPEAMT enhanced the drought tolerance of transgenic tobacco.

scholarly journals Dimerization and oligomerization of DNA-assembled building blocks for controlled multi-motion in high-order architectures

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Ling Xin ◽  
Xiaoyang Duan ◽  
Na Liu
Keyword(s):  
Building Block ◽  
Degrees Of Freedom ◽  
Building Blocks ◽  
Single Type ◽  
Hierarchical Assembly ◽  
Optical Responses ◽  
Self Association ◽  
Living Organisms ◽  
Order Structures ◽  
Chiral System

AbstractIn living organisms, proteins are organized prevalently through a self-association mechanism to form dimers and oligomers, which often confer new functions at the intermolecular interfaces. Despite the progress on DNA-assembled artificial systems, endeavors have been largely paid to achieve monomeric nanostructures that mimic motor proteins for a single type of motion. Here, we demonstrate a DNA-assembled building block with rotary and walking modules, which can introduce new motion through dimerization and oligomerization. The building block is a chiral system, comprising two interacting gold nanorods to perform rotation and walking, respectively. Through dimerization, two building blocks can form a dimer to yield coordinated sliding. Further oligomerization leads to higher-order structures, containing alternating rotation and sliding dimer interfaces to impose structural twisting. Our hierarchical assembly scheme offers a design blueprint to construct DNA-assembled advanced architectures with high degrees of freedom to tailor the optical responses and regulate multi-motion on the nanoscale.

scholarly journals Klebsiella Phage ΦK64-1 Encodes Multiple Depolymerases for Multiple Host Capsular Types

2017 ◽  
Vol 91 (6) ◽  
Author(s):  
Yi-Jiun Pan ◽  
Tzu-Lung Lin ◽  
Ching-Ching Chen ◽  
Yun-Ting Tsai ◽  
Yi-Hsiang Cheng ◽  
...  
Keyword(s):  
Sequence Similarity ◽  
Amino Acid Sequence Similarity ◽  
Gene Products ◽  
Capsular Type ◽  
Expression And Purification ◽  
Content Type ◽  
Infection Mechanisms ◽  
Host Infection ◽  
Encoding Genes ◽  
Tail Fibers

ABSTRACT The genome of the multihost bacteriophage ΦK64-1, capable of infecting Klebsiella capsular types K1, K11, K21, K25, K30, K35, K64, and K69, as well as new capsular types KN4 and KN5, was analyzed and revealed that 11 genes (S1-1, S1-2, S1-3, S2-1, S2-2, S2-3, S2-4, S2-5, S2-6, S2-7, and S2-8) encode proteins with amino acid sequence similarity to tail fibers/spikes or lyases. S2-5 previously was shown to encode a K64 capsule depolymerase (K64dep). Specific capsule-degrading activities of an additional eight putative capsule depolymerases (S2-4 against K1, S1-1 against K11, S1-3 against K21, S2-2 against K25, S2-6 against K30/K69, S2-3 against K35, S1-2 against KN4, and S2-1 against KN5) was demonstrated by expression and purification of the recombinant proteins. Consistent with the capsular type-specific depolymerization activity of these gene products, phage mutants of S1-2, S2-2, S2-3, or S2-6 lost infectivity for KN4, K25, K35, or K30/K69, respectively, indicating that capsule depolymerase is crucial for infecting specific hosts. In conclusion, we identified nine functional capsule depolymerase-encoding genes in a bacteriophage and correlated activities of the gene products to all ten hosts of this phage, providing an example of type-specific host infection mechanisms in a multihost bacteriophage. IMPORTANCE We currently identified eight novel capsule depolymerases in a multihost Klebsiella bacteriophage and correlated the activities of the gene products to all hosts of this phage, providing an example of carriage of multiple depolymerases in a phage with a wide capsular type host spectrum. Moreover, we also established a recombineering system for modification of Klebsiella bacteriophage genomes and demonstrated the importance of capsule depolymerase for infecting specific hosts. Based on the powerful tool for modification of phage genome, further studies can be conducted to improve the understanding of mechanistic details of Klebsiella phage infection. Furthermore, the newly identified capsule depolymerases will be of great value for applications in capsular typing.

scholarly journals Site-directed mutagenesis at aspartate and glutamate residues of xylanase from Bacillus pumilus

1992 ◽  
Vol 288 (1) ◽  
pp. 117-121 ◽  
Author(s):  
E P Ko ◽  
H Akatsuka ◽  
H Moriyama ◽  
A Shinmyo ◽  
Y Hata ◽  
...  
Keyword(s):  
Amino Acids ◽  
Reaction Mechanism ◽  
Amino Acid ◽  
Bacillus Pumilus ◽  
Specific Activity ◽  
Sequence Similarity ◽  
Site Directed Mutagenesis ◽  
Dimensional Structure ◽  
Amino Acid Sequence Similarity ◽  
Directed Mutagenesis

To elucidate the reaction mechanism of xylanase, the identification of amino acids essential for its catalysis is of importance. Studies have indicated the possibility that the reaction mechanism of xylanase is similar to that of hen's egg lysozyme, which involves acidic amino acid residues. On the basis of this assumption, together with the three-dimensional structure of Bacillus pumilus xylanase and its amino acid sequence similarity to other xylanases of different origins, three acidic amino acids, namely Asp-21, Glu-93 and Glu-182, were selected for site-directed mutagenesis. The Asp residue was altered to either Ser or Glu, and the Glu residues to Ser or Asp. The purified mutant xylanases D21E, D21S, E93D, E93S, E182D and E182S showed single protein bands of about 26 kDa on SDS/PAGE. C.d. spectra of these mutant enzymes show no effect on the secondary structure of xylanase, except that of D21E, which shows a little variation. Furthermore, mutations of Glu-93 and Glu-182 resulted in a drastic decrease in the specific activity of xylanase as compared with mutation of Asp-21. On the basis of these results we propose that Glu-93 and Glu-182 are the best candidates for the essential catalytic residues of xylanase.

Na(+)-independent transport (uniport) of amino acids and glucose in mammalian cells.

1994 ◽  
Vol 196 (1) ◽  
pp. 93-108
Author(s):  
D K Kakuda ◽  
C L MacLeod
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Mammalian Cells ◽  
Glucose Transporter ◽  
Sequence Similarity ◽  
Amino Acid Sequence Similarity ◽  
Amino Acid Transporters ◽  
Cationic Amino Acid ◽  
Transporter Family ◽  
Share Amino Acid Sequence

Recent advances have made possible the isolation of the genes and their cDNAs encoding Na(+)-independent amino acid transporters. Two classes of amino acid 'uniporters' have been isolated. One class contains the mCAT (murine cationic amino acid transporter) gene family that encodes proteins predicted to span the membrane 12-14 times and exhibits structural properties similar to the GLUT (glucose transporter) family and to other well-known transporters. The other class consists of two known genes, rBAT (related to B system amino acid transporters) and 4F2hc, that share amino acid sequence similarity with alpha-amylases and alpha-glucosidases. They are type II glycoproteins predicted to span the membrane only once, yet they mediate the Na(+)-independent transport of cationic and zwitterionic amino acids in Xenopus oocytes. Mutations in the human rBAT gene have been identified by Palacín and his co-workers in several families suffering from a heritable form of cystinuria. This important finding clearly establishes a key role for rBAT in cystine transport. The two classes of amino acid transporters are compared with the well-studied GLUT family of Na(+)-independent glucose transporters.

History, Diagnosis, and Treatment of Coronavirus Disease 2019 (COVID-19)

Coronaviruses ◽  
2021 ◽  
Vol 02 ◽  
Author(s):  
Amaresh Mishra ◽  
Nisha Nair ◽  
Vishwas Tripathi ◽  
Yamini Pathak ◽  
Jaseela Majeed
Keyword(s):  
Amino Acid ◽  
Severe Acute Respiratory Syndrome ◽  
Sequence Similarity ◽  
Neurological Complications ◽  
Amino Acid Sequences ◽  
World Health ◽  
Amino Acid Sequence Similarity ◽  
Effective Prevention ◽  
Short Period ◽  
The World

: The Coronavirus Disease 2019 (COVID-19), also known as a novel coronavirus (2019-nCoV), reportedly originated from Wuhan City, Hubei Province, China. Coronavirus Disease 2019 rapidly spread all over the world within a short period. On January 30th, 2020, the World Health Organization (WHO) declared it a global epidemic. COVID-19 is a severe acute respiratory syndrome coronavirus (SARS-CoV) virus that evolves to respiratory, hepatic, gastrointestinal, and neurological complications, and eventually death. SARS-CoV and the Middle East Respiratory Syndrome coronavirus (MERS-CoV) genome sequences similar identity with 2019-nCoV or severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, few amino acid sequences of 2019-nCoV differ from SARS-CoV and MERS-CoV. COVID-19 shares about 90% amino acid sequence similarity with SARS-CoV. Effective prevention methods should be taken in order to control this pandemic situation. Till now, there are no effective treatments available to treat COVID-19. This review provides information regarding COVID-19 history, epidemiology, pathogenesis, and molecular diagnosis. Also, we focus on the development of vaccines in the management of this COVID-19 pandemic and limiting the spread of the virus.

The gene encoding a major component of the lateral elements of synaptonemal complexes of the rat is related to X-linked lymphocyte-regulated genes

1994 ◽  
Vol 14 (2) ◽  
pp. 1137-1146
Author(s):  
J H Lammers ◽  
H H Offenberg ◽  
M van Aalderen ◽  
A C Vink ◽  
A J Dietrich ◽  
...  
Keyword(s):  
Amino Acid ◽  
Sequence Similarity ◽  
Sodium Dodecyl ◽  
Coiled Coil ◽  
Amino Acid Identity ◽  
Male Rat ◽  
Amino Acid Sequence Similarity ◽  
Gene Encoding ◽  
Synaptonemal Complexes ◽  
Complex Protein

The lateral elements of synaptonemal complexes (SCs) of the rat contain major components with relative electrophoretic mobilities (M(r)S) of 30,000 and 33,000. After one-dimensional separation of SC proteins on polyacrylamide-sodium dodecyl sulfate gels, these components show up as two broad bands. These bands contain closely related proteins, as judged from their peptide maps and immunological reactivity. Using affinity-purified polyclonal anti-30,000- and anti-33,000-M(r) component antibodies, we isolated a cDNA encoding at least one of the 30,000- or 33,000-M(r) SC components. The protein predicted from the nucleotide sequence of the cDNA, called SCP3 (for synaptonemal complex protein 3), has a molecular mass of 29.7 kDa and a pI value of 9.4. It has a potential nucleotide binding site and contains stretches that are predicted to be capable of forming coiled-coil structures. In the male rat, the gene encoding SCP3 is transcribed exclusively in the testis. SCP3 has significant amino acid similarity to the pM1 protein, which is one of the predicted products of an X-linked lymphocyte-regulated gene family of the mouse: there are 63% amino acid sequence similarity and 35% amino acid identity between the SCP3 and pM1 proteins. However, SCP3 differs from pM1 in several respects, and whether the proteins fulfill related functions is still an open question.

scholarly journals Colocality to Cofunctionality: Eukaryotic Gene Neighborhoods as a Resource for Function Discovery

2020 ◽  
Author(s):  
Fatima Foflonker ◽  
Crysten E Blaby-Haas
Keyword(s):  
Green Algae ◽  
Sequence Similarity ◽  
Phosphoglycerate Kinase ◽  
Orthologous Gene ◽  
Model Organisms ◽  
Comparative Genomic ◽  
Evolutionary Origins ◽  
Eukaryotic Gene ◽  
Arsenic Detoxification ◽  
Function Discovery

Abstract Diverging from the classic paradigm of random gene order in eukaryotes, gene proximity can be leveraged to systematically identify functionally related gene neighborhoods in eukaryotes, utilizing techniques pioneered in bacteria. Current methods of identifying gene neighborhoods typically rely on sequence similarity to characterized gene products. However, this approach is not robust for nonmodel organisms like algae, which are evolutionarily distant from well-characterized model organisms. Here, we utilize a comparative genomic approach to identify evolutionarily conserved proximal orthologous gene pairs conserved across at least two taxonomic classes of green algae. A total of 317 gene neighborhoods were identified. In some cases, gene proximity appears to have been conserved since before the streptophyte–chlorophyte split, 1,000 Ma. Using functional inferences derived from reconstructed evolutionary relationships, we identified several novel functional clusters. A putative mycosporine-like amino acid, “sunscreen,” neighborhood contains genes similar to either vertebrate or cyanobacterial pathways, suggesting a novel mosaic biosynthetic pathway in green algae. One of two putative arsenic-detoxification neighborhoods includes an organoarsenical transporter (ArsJ), a glyceraldehyde 3-phosphate dehydrogenase-like gene, homologs of which are involved in arsenic detoxification in bacteria, and a novel algal-specific phosphoglycerate kinase-like gene. Mutants of the ArsJ-like transporter and phosphoglycerate kinase-like genes in Chlamydomonas reinhardtii were found to be sensitive to arsenate, providing experimental support for the role of these identified neighbors in resistance to arsenate. Potential evolutionary origins of neighborhoods are discussed, and updated annotations for formerly poorly annotated genes are presented, highlighting the potential of this strategy for functional annotation.

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