scholarly journals Distribution of the ribosome associated endonuclease Rae1 and the potential role of conserved amino acids in codon recognition

RNA Biology ◽  
2018 ◽  
pp. 1-6 ◽  
Author(s):  
Ciarán Condon ◽  
Jéremie Piton ◽  
Frédérique Braun
Keyword(s):  
Amino Acids ◽  
Potential Role ◽  
Codon Recognition ◽  
Conserved Amino Acids

Clostridium thermocellumXyn10B Carbohydrate-Binding Module 22-2:  The Role of Conserved Amino Acids in Ligand Binding†,‡

Biochemistry ◽  
2001 ◽  
Vol 40 (31) ◽  
pp. 9167-9176 ◽  
Author(s):  
Hefang Xie ◽  
Harry J. Gilbert ◽  
Simon J. Charnock ◽  
Gideon J. Davies ◽  
Michael P. Williamson ◽  
...  
Keyword(s):  
Amino Acids ◽  
Ligand Binding ◽  
Carbohydrate Binding ◽  
Carbohydrate Binding Module ◽  
Conserved Amino Acids

scholarly journals Restoration of high-level transport activity by human reduced folate carrier/ThTr1 thiamine transporter chimaeras: role of the transmembrane domain 6/7 linker region in reduced folate carrier function

2003 ◽  
Vol 369 (1) ◽  
pp. 31-37 ◽  
Author(s):  
Xiang Y. LIU ◽  
Teah L. WITT ◽  
Larry H. MATHERLY
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Plasma Membranes ◽  
Transmembrane Domain ◽  
K562 Cells ◽  
Reduced Folate Carrier ◽  
Wild Type ◽  
Linker Region ◽  
Conserved Amino Acids

The reduced folate carrier (RFC; SLC19A1) is closely related to the thiamine transporter, SLC19A2 (ThTr1). Hydropathy models for these homologous transporters predict up to 12 transmembrane domains (TMDs), with internally oriented N- and C-termini and a large central loop between TMDs 6 and 7. The homologies are localized mostly in the TMDs. However, there is little similarity in their N- and C-terminal domains and the central peptide linkers connecting putative TMDs 1—6 and TMDs 7—12. To explore the functional role of the 61-amino acid central linker in the human RFC (hRFC), we introduced deletions of 49 and 60 amino acids into this region, differing by the presence of a stretch of 11 highly conserved amino acids between the human and rodent RFCs (positions 204—214). An additional hRFC construct was prepared in which only the 11 conserved amino acids were deleted. The resulting hRFCD215—R263Δ, hRFCK204—R263Δ and hRFCK204—R214Δ proteins were transfected into transport-impaired K562 cells. The deletion constructs were all expressed in plasma membranes; however, they were completely inactive for methotrexate and (6S)5-formyl tetrahydrofolate transport. Insertion of non-homologous 73- and 84-amino acid fragments from the structurally analogous ThTr1 linker region into position 204 of hRFCK204—R263Δ restored low levels of transport (16—21% of the wild type). Insertion of the ThTr1 linkers into hRFCD215—R263Δ at position 215 restored 60—80% of wild-type levels of transport. Collectively, our results suggest that the role of the hRFC linker peptide is to provide the proper spatial orientation between the two halves of the hRFC protein for optimal function, and that this is largely independent of amino acid sequence. Our results also demonstrate a critical transport role for the stretch of 11 conserved amino acids starting at position 204 of hRFC.

scholarly journals Endothelin in health and disease

2004 ◽  
Vol 4 (3) ◽  
pp. 31-34 ◽  
Author(s):  
Emina Nakaš-Ićindić ◽  
Asija Začiragić ◽  
Almira Hadžović ◽  
Nešina Avdagić
Keyword(s):  
Nitric Oxide ◽  
Amino Acids ◽  
Calcium Ions ◽  
Potential Role ◽  
Cyclic Guanosine Monophosphate ◽  
Guanosine Monophosphate ◽  
Health And Disease ◽  
Endothelin 3 ◽  
Stimulation Of

Endothelin is a recently discovered peptide composed of 21 amino acids. There are three endothelin isomers: endothelin -1 (ET-1), endothelin -2 (ET-2) and endothelin - 3 (ET-3). In humans and animals levels of ET-1, ET-2, ET-3 and big endothelin in blood range from 0,3 to 3 pg/ml. ET-1, ET-2 and ET-3 act by binding to receptors. Two main types of the receptors for endothelins exist and they are referred to as A and B type receptors. Different factors can stimulate or inhibit production of endothelin by endothelial cells. Mechanical stimulation of endothehum, thrombin, calcium ions, epinephrine, angiotensin II, vasopressin, dopamine, cytokines, growth factors stimulate the production of endothelin whereas nitric oxide, cyclic guanosine monophosphate, atrial natriuretic peptide, prostacyclin, bradykinin inhibit its production. Endothelins have different physiological roles in human body but at the same time their actions are involved in the pathogenesis of many diseases.The aim of this review was to present some of, so far, the best studied physiological roles of endothelin and to summarize evidence supporting the potential role of ET in the pathogenesis of certain diseases.

scholarly journals The Cipher Code of Simple Sequence Repeats in “Vampire Pathogens”

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Geng Zou ◽  
Bernardo Bello-Orti ◽  
Virginia Aragon ◽  
Alexander W. Tucker ◽  
Rui Luo ◽  
...  
Keyword(s):  
Amino Acids ◽  
Simple Sequence Repeats ◽  
Potential Role ◽  
Gc Content ◽  
Nucleotide Metabolism ◽  
Coding Regions ◽  
Purine Nucleotide Metabolism ◽  
Go Terms ◽  
Simple Sequence

Abstract Blood inside mammals is a forbidden area for the majority of prokaryotic microbes; however, red blood cells tropism microbes, like “vampire pathogens” (VP), succeed in matching scarce nutrients and surviving strong immunity reactions. Here, we found VP of Mycoplasma, Rhizobiales and Rickettsiales showed significantly higher counts of (AG)n dimeric simple sequence repeats (Di-SSRs) in the genomes, coding and non-coding regions than non Vampire Pathogens (N_VP). Regression analysis indicated a significant correlation between GC content and the span of (AG)n-Di-SSR variation. Gene Ontology (GO) terms with abundance of (AG)3-Di-SSRs shared by the VP strains were associated with purine nucleotide metabolism (FDR < 0.01), indicating an adaptation to the limited availability of purine and nucleotide precursors in blood. Di-amino acids coded by (AG)n-Di-SSRs included all three six-fold code amino acids (Arg, Leu and Ser) and significantly higher counts of Di-amino acids coded by (AG)3, (GA)3 and (TC)3 in VP than N_VP. Furthermore, significant differences (P < 0.001) on the numbers of triplexes formed from (AG)n-Di-SSRs between VP and N_VP in Mycoplasma suggested the potential role of (AG)n-Di-SSRs in gene regulation.

scholarly journals Internal Point Mutations of the Capsid Modify the Serotype of Rice Yellow Mottle Virus

2005 ◽  
Vol 79 (7) ◽  
pp. 4407-4414 ◽  
Author(s):  
Eugénie Hébrard ◽  
Agnès Pinel-Galzi ◽  
Vincent Catherinot ◽  
Gilles Labesse ◽  
Christophe Brugidou ◽  
...  
Keyword(s):  
Amino Acids ◽  
Molecular Diversity ◽  
Potential Role ◽  
Infectious Clone ◽  
Point Mutations ◽  
Mottle Virus ◽  
Rice Yellow Mottle Virus ◽  
Internal Point ◽  
Yellow Mottle

ABSTRACT Rice yellow mottle virus is classified in five major serotypes; the molecular diversity of the coat protein (CP) is well established, but the amino acids involved in the recognition by discriminant monoclonal antibodies (MAbs) remain unknown. Reconstruction of a phylogenetic tree and sequence alignment of the CP gene of a sample representative of the continental-large diversity were used to identify 10 serospecific amino acids (i.e., conserved in all isolates belonging to the same serotype and distinct in other serotypes). Positions occupied by serospecific residues were localized on the crystal structure of the CP monomer and on modeled capsomers. Structural, molecular, and serological properties of each serotype were analyzed, and subsequently, hypotheses on the potential role of amino acids in discriminating reactions with antibodies were formulated. The residues 114 and 115 (serospecific of Sr1) and 190 (serospecific of Sr2) were localized on the outer surface of the capsid and might be directly involved in the immunoreactivity with MAb D and MAb A, respectively. In contrast, residues 180 (Sr3) and 178 (Sr5) lay within the inner surface of the capsid. To understand the role of these internal positions in the recognition with the antibodies, two substitutions (T180K and G178D) were introduced in the CP of an infectious clone. These mutations modified the antigenicity with MAb G and MAb E discriminating Sr3 and Sr5, respectively, while the reaction with MAb D remained unaffected. This result suggests an indirect effect of these two internal mutations on local immunostructure while the global structure was maintained.

Sign in / Sign up

Export Citation Format

Share Document