scholarly journals Snake venom disintegrins: novel dimeric disintegrins and structural diversification by disulphide bond engineering

2003 ◽  
Vol 372 (3) ◽  
pp. 725-734 ◽  
Author(s):  
Juan J. CALVETE ◽  
M. Paz MORENO-MURCIANO ◽  
R. David G. THEAKSTON ◽  
Dariusz G. KISIEL ◽  
Cezary MARCINKIEWICZ

We report the isolation and amino acid sequences of six novel dimeric disintegrins from the venoms of Vipera lebetina obtusa (VLO), V. berus (VB), V. ammodytes (VA), Echis ocellatus (EO) and Echis multisquamatus (EMS). Disintegrins VLO4, VB7, VA6 and EO4 displayed the RGD motif and inhibited the adhesion of K562 cells, expressing the integrin α5β1 to immobilized fibronectin. A second group of dimeric disintegrins (VLO5 and EO5) had MLD and VGD motifs in their subunits and blocked the adhesion of the α4β1 integrin to vascular cell adhesion molecule 1 with high selectivity. On the other hand, disintegrin EMS11 inhibited both α5β1 and α4β1 integrins with almost the same degree of specificity. Comparison of the amino acid sequences of the dimeric disintegrins with those of other disintegrins by multiple-sequence alignment and phylogenetic analysis, in conjunction with current biochemical and genetic data, supports the view that the different disintegrin subfamilies evolved from a common ADAM (adisintegrin and metalloproteinase-like) scaffold and that structural diversification occurred through disulphide bond engineering.

2013 ◽  
Vol 5 (3) ◽  
pp. 14
Author(s):  
Michael Andrew Meyer

<p>The JC polyoma viral coat protein VP1 was analyzed for amino acid sequences homologies to the IDSP sequence which mediates binding of VLA-4 (integrin alpha 4) to vascular cell adhesion molecule 1. Although the full sequence was not found, a DSP sequence was located near the critical arginine residue linked to infectivity of the virus and binding to sialic acid containing molecules such as integrins (3). For the JC polyoma virus, a DSP sequence was found at residues 70, 71 and 72 with homology also noted for the mouse polyoma virus and SV40 virus. Three dimensional modeling of the VP1 molecule suggests that the DSP loop has an accessible site for interaction from the external side of the assembled viral capsid pentamer.</p>


2020 ◽  
Vol 17 (1) ◽  
pp. 59-77
Author(s):  
Anand Kumar Nelapati ◽  
JagadeeshBabu PonnanEttiyappan

Background:Hyperuricemia and gout are the conditions, which is a response of accumulation of uric acid in the blood and urine. Uric acid is the product of purine metabolic pathway in humans. Uricase is a therapeutic enzyme that can enzymatically reduces the concentration of uric acid in serum and urine into more a soluble allantoin. Uricases are widely available in several sources like bacteria, fungi, yeast, plants and animals.Objective:The present study is aimed at elucidating the structure and physiochemical properties of uricase by insilico analysis.Methods:A total number of sixty amino acid sequences of uricase belongs to different sources were obtained from NCBI and different analysis like Multiple Sequence Alignment (MSA), homology search, phylogenetic relation, motif search, domain architecture and physiochemical properties including pI, EC, Ai, Ii, and were performed.Results:Multiple sequence alignment of all the selected protein sequences has exhibited distinct difference between bacterial, fungal, plant and animal sources based on the position-specific existence of conserved amino acid residues. The maximum homology of all the selected protein sequences is between 51-388. In singular category, homology is between 16-337 for bacterial uricase, 14-339 for fungal uricase, 12-317 for plants uricase, and 37-361 for animals uricase. The phylogenetic tree constructed based on the amino acid sequences disclosed clusters indicating that uricase is from different source. The physiochemical features revealed that the uricase amino acid residues are in between 300- 338 with a molecular weight as 33-39kDa and theoretical pI ranging from 4.95-8.88. The amino acid composition results showed that valine amino acid has a high average frequency of 8.79 percentage compared to different amino acids in all analyzed species.Conclusion:In the area of bioinformatics field, this work might be informative and a stepping-stone to other researchers to get an idea about the physicochemical features, evolutionary history and structural motifs of uricase that can be widely used in biotechnological and pharmaceutical industries. Therefore, the proposed in silico analysis can be considered for protein engineering work, as well as for gout therapy.


Author(s):  
Sona. S Dev ◽  
P. Poornima ◽  
Akhil Venu

Eggplantor brinjal (Solanum melongena L.), is highly susceptible to various soil-borne diseases. The extensive use of chemical fungicides to combat these diseases can be minimized by identification of resistance gene analogs (RGAs) in wild species of cultivated plants.In the present study, degenerate PCR primers for the conserved regions ofnucleotide binding site-leucine rich repeat (NBS-LRR) were used to amplify RGAs from wild relatives of eggplant (Black nightshade (Solanum nigrum), Indian nightshade (Solanumviolaceum)and Solanu mincanum) which showed resistance to the bacterial wilt pathogen, Ralstonia solanacearumin the preliminary investigation. The amino acid sequence of the amplicons when compared to each other and to the amino acid sequences of known RGAs deposited in Gen Bank revealed significant sequence similarity. The phylogenetic analysis indicated that they belonged to the toll interleukin-1 receptors (TIR)-NBS-LRR type R-genes. Multiple sequence alignment with other known R genes showed significant homology with P-loop, Kinase 2 and GLPL domains of NBS-LRR class genes. There has been no report on R genes from these wild eggplants and hence the diversity analysis of these novel RGAs can lead to the identification of other novel R genes within the germplasm of different brinjal plants as well as other species of Solanum.


2007 ◽  
Vol 88 (12) ◽  
pp. 3445-3451 ◽  
Author(s):  
Min Sook Hwang ◽  
Kyung Nam Kim ◽  
Jeong Hyun Lee ◽  
Young In Park

The cucumber mosaic virus (CMV)-encoded 3a movement protein (MP) is indispensable for CMV movement in plants. We have previously shown that MP interacts directly with the CMV-encoded 2a polymerase protein in vitro. Here, we further dissected this interaction and determined the amino acid sequences that are responsible for the MP and 2a polymerase protein interaction. Both the N-terminal 21 amino acids and the central GDD motif of the 2a polymerase protein were important for interacting with the MP. Although each of the regions alone was sufficient for the interaction with MP, quantitative yeast two-hybrid analyses showed that they acted synergistically to enhance the binding affinity. The MP N-terminal 20 amino acids were sufficient for interacting with the 2a polymerase protein, and the serine residue at position 14 played a critical role in the interaction. Multiple sequence alignment showed that the 2a protein interacting regions and the serine at position 14 in the MP are highly conserved among subgroup I and II CMV isolates.


Author(s):  
Yong-Chan Kim ◽  
Byung-Hoon Jeong

AbstractInterferon-induced transmembrane protein 3 (IFITM3) plays a pivotal role in antiviral capacity in several species. However, to date, investigations of the IFITM3 protein in cattle have been rare. According to recent studies, interspecific differences in the IFITM3 protein result in several unique features of the IFITM3 protein relative to primates and birds. Thus, in the present study, we investigated the bovine IFITM3 protein based on nucleotide and amino acid sequences to find its distinct features. We found that the bovine IFITM3 gene showed a significantly different length and homology relative to other species, including primates, rodents and birds. Phylogenetic analyses indicated that the bovine IFITM3 gene and IFITM3 protein showed closer evolutionary distance with primates than with rodents. However, cattle showed an independent clade among primates, rodents and birds. Multiple sequence alignment of the IFITM3 protein indicated that the bovine IFITM3 protein contains 36 bovine-specific amino acids. Notably, the bovine IFITM3 protein was predicted to prefer inside-to-outside topology of intramembrane domain 1 (IMD1) and inside-to-outside topology of transmembrane domain 2 by TMpred and three membrane embedding domains according to the SOSUI system.


1976 ◽  
Vol 155 (1) ◽  
pp. 5-17 ◽  
Author(s):  
K B M Reid

1. Digestion of human subcomponent C1q with pepsin at pH4.45 for 20h at 37 degrees C fragmented most of the non-collagen-like amino acid sequences in the molecule to small peptides, whereas the entire regions of collagen-like sequence that comprised 38% by weight of the subcomponent C1q were left intact. 2. The collagen-like fraction of the digest was eluted in the void volume of a Sephadex G-200 column, was was showm to be composed of two major fragments when examined by electrophoresis on polyacrylamide gels run in buffers containing sodium dodecyl sulphate. These fragments were separated on CM-cellulose at pH4.9 in buffers containing 7.5M-urea. 3. Human subcomponent C1q on reduction and alkylation yields equimolar amounnts of three chains, which have been designated A, B and C [Reid et al. (1972) Biochem. J. 130, 749-763]. One of the pepsin fragments was shown to be composed of the N-terminal 95 residues of the A chain linked, via residue A4, by a single disulphide bond to a residue in the sequence B2-B6 in the N-terminal 91 residues of the B chain. The second pepsin fragment was shown to be composed of a disulphide-linked dimer of the N-terminal 94 residues of the C chain, the only disulphide bond being located at residue C4.4. The mol. wts. of the unoxidized and oxidized pepsin fragments were estimated from their amino acid compositions to be 20 000 and 18 200 for the A-B and C-C dimers and 11 400, 8800 and 9600 for the collagen-like fragments of the A, B and C chains respectively. Estimation of the molecular weights of the peptic fragments by polyacrylamide-gel electrophoresis run in the presence of sodium dodecyl sulphate gave values that were approx. 50% higher than expected from the amino acid sequence data. This is probably due to the high collagen-like sequence content of these fragments.


Author(s):  
Samira A. Osman ◽  
Walaa A. Ramadan

Abstract Background The genus Triticum L. includes diploid, tetraploid, and hexaploid species. DNA barcoding is a new method to identify plant taxa by using short sequences of DNA and within a short time. In this investigation, we determined a phylogenetic analysis of 20 different Triticum species by partial chloroplast Maturase encoding gene (matK). Materials and methods Twenty accessions of different Triticum species diploid, tetraploid, and hexaploid were obtained from different countries. Genomic DNA was isolated from young leaves of studied samples and then used as a template for PCR reaction. PCR products were checked by electrophoresis, purified, sequenced, and submitted in the GenBank nucleotide sequence database, the nucleotide sequence was translated into an amino acid sequence. The nucleotide and amino acid sequences were aligned with Clustal W multiple sequence alignment programs to obtain the phylogenetic tree depending on two statistical data analysis such as bootstrapping and pairwise distance from both nucleotide and amino acid sequences. Results The phylogenetic tree obtained from both nucleotide and amino acid sequences divided the 20 Triticum species into two groups, A and B. Group A represented the diploid Triticum species. Group B was divided into two subgroup, I and II. Subgroup I represented the hexaploid Triticum species and subgroup II represented the tetraploid species. Conclusion The matK gene sequence has a critical role in discriminating the closely related Triticum species. So these sequences could be used as a DNA barcode for detecting the evolutionary history of Triticum species.


2013 ◽  
Vol 2 (3) ◽  
pp. 121-136 ◽  
Author(s):  
Jae-Hyun Kim ◽  
Young-Soo Kim ◽  
Soo-Won Jang ◽  
Yong-Ho Jeon

We isolated tomato spotted wilt virus (TSWV-KP) from a diseased Capsicum annuum var. grossum with malformed leaves and necrotic spotted fruits. TSWV-KP produced necrosis or necrotic ring spots on inoculated leaves along with mosaic, vein necrosis, or death on the upper leaves on Datura stramonium, Nicotiana clevarandii, N. rustica, and N. tabacum cvs. Ultrastructurally, typical tospovirus particles were observed in the cytoplasm. The virion contained three molecules of genomic RNAs of approximately 9.0, 4.9, and 3.0 kb. The nucleocapsid (N) protein of the purified virion migrated as a single band with ~29 kDa molecular weight in SDS-PAGE. Complete nucleotide sequences of the large (L) genome segments of TSWV-KP were determined. Defective forms of L-RNA containing core polymerase regions were observed. L-RNA (8,917 nucleotides) contained a single open reading frame (ORF) in the viral complementary (vc) strand and encoded a 330-kDa protein. The L-protein had high identity in the “core-polymerase domain” with the corresponding regions of other tospoviruses. The complete nucleotide sequence of TSWV-KP medium-sized (M) RNA comprised 4,768 nucleotides and indicated a typical tospovirus with two genes in ambisense arrangement. The vRNA OFR coded for a potential cell-to-cell movement (NSm) 34.8-kDa protein; and the vcRNA ORF, for the viral glycoprotein (G1/G2) 128.0-kDa precursor. Multiple sequence alignment of the M-RNA showed highest homologies to TSWV-BR01. Amino acid sequences of TSWV-KP NSm and G1/G2 exhibited 48.7–85.3% and 34.9–96.2% identity, respectively. TSWV-KP small (S) RNA comprised 2,991 nucleotides with ambisense coding strategy. The sequence contained two ORFs—one in the viral sense, encoding a protein with predicted 52.4-kDa Mr; and another in the viral complementary sense, encoding the viral nucleocapsid protein of 28.8-kDa Mr. Amino acid sequences of TSWV-KP of S-RNA NSs and N exhibited 35.9–87.9% and 19.9–98.4% identity, respectively.


1989 ◽  
Vol 261 (2) ◽  
pp. 551-560 ◽  
Author(s):  
J J Calvete ◽  
M V Alvarez ◽  
G Rivas ◽  
C L Hew ◽  
A Henschen ◽  
...  

The single interchain disulphide bond in platelet glycoprotein IIb (GPIIb) is accessible to extracellular reductants, and selective cleavage does not liberate GPIIb alpha from platelet plasma membrane, confirming that non-covalent interactions contribute to maintaining attachment of this subunit to the membrane. Eosin-maleimide labelling of isolated GPIIb after selective cleavage of this interchain disulphide bond, followed by full reduction and alkylation, CNBr cleavage, and analysis of the cleavage products allowed us to establish that this interchain disulphide bridge is formed between GPIIb beta (GPIIb beta-subunit) Cys-9 and GPIIb alpha Cys-826, and this conclusion was confirmed by independent routes. The other two cysteines of GPIIb beta (Cys-14 and Cys-19) form the single intrachain disulphide bond in this subunit. Last, the intrachain disulphides in GPIIb alpha (GPIIb alpha-subunit) are distributed in four main peptide domains which are not disulphide-bonded among themselves. The linear epitope for monoclonal antibody M1 is localized between Pro-4 and Met-24 (or Met-31) of GPIIb beta. The linear epitope for M3 is situated between Cys-826 and the C-terminus of GPIIb alpha. The M4 epitope is also linear and localized somewhere between residues 115 and 285 of GPIIb alpha. Finally, the epitopes for M5 and M6 are somewhere between Cys-608 and Met-704, within a 35 kDa membrane-bound chymotryptic product of digestion of GPIIb in whole platelets. The N-terminal amino acid sequences determined for eight different cleavage products of GPIIb alpha and GPIIb beta agree with the corresponding amino acid sequences predicted by cDNA sequence for human-erythroleukaemic-cell GPIIb [Poncz, Eisman, Heindenreich, Silver, Vilaire, Surrey, Schwartz & Bennett (1987) J. Biol. Chem. 262, 8476-8482].


2019 ◽  
Vol 16 (3) ◽  
pp. 210-221
Author(s):  
Sarita Devi ◽  
Savitri ◽  
Tilak Raj ◽  
Nikhil Sharma ◽  
Wamik Azmi

Background:L-glutaminase enzyme belongs to the family of hydrolases, those acting on carbon-nitrogen bonds other than peptide bonds, specifically in linear amides. Protein L-glutaminase, which converts amino acid glutamine to a glutamate residue, is useful as antileukemic agent, antiretroviral agent and a new food-processing enzyme.Objective:The sequences representing L-glutaminase from extremophiles were analyzed for different physico-chemical properties and to relate these observed differences to their extremophilic properties, phylogenetic tree construction and the evolutionary relationship among them.Methods:In this work, in silico analysis of amino acid sequences of extremophilic (thermophile, halophile and psychrophiles) proteins has been done. The physiochemical properties of these four groups of proteins for L-glutaminase also differ in number of amino acids, aliphatic index and grand average of hydropathicity (GRAVY).Result:The GRAVY was found to be significantly high in thermophilic (2.29 fold) and psychrophilic bacteria (3.3 fold) as compare to mesophilic bacteria. The amino acid Cys (C) was found to be statistically significant in mesophilic bacteria (approximately or more than 3 fold) as compared to the abundance of this amino acid in extremophilic bacteria.Conclusion:Multiple sequence alignment revealed the domain/motif for glutaminase that consists of Ser-74, Lys-77, Asn-126, Lys-268, and Ser-269, which is highly conserved in all microorganisms.


Sign in / Sign up

Export Citation Format

Share Document