Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 6

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

Discrete dynamic system oriented on the formation of prebiotic dipeptides from Rode's experiment

100%
Polanco C., Samaniego J., Buhse T., Castañón González J.
Acta Biochimica Polonica
|
2014
|
vol. 61
|
issue 4
717-726
EN
This work attempts to rationalize the possible prebiotic profile of the first dipeptides of about 4 billion years ago based on a computational discrete dynamic system that uses the final yields of the dipeptides obtained in Rode's experiments of salt-induced peptide formation (Rode et al., 1999, Peptides 20: 773-786). The system built a prebiotic scenario that allowed us to observe that (i) the primordial peptide generation was strongly affected by the abundances of the amino acid monomers, (ii) small variations in the concentration of the monomers have almost no effect on the final distribution pattern of the dipeptides and (iii) the most plausible chemical reaction of prebiotic peptide bond formation can be linked to Rode's hypothesis of a salt-induced scenario. The results of our computational simulations were related to former simulations of the Miller, and Fox & Harada experiments on amino acid monomer and oligomer generation, respectively, offering additional information to our approach.
2
Content available remote

Possible computational filter to detect proteins associated to influenza A subtype H1N1

100%
Polanco C., Buhse T., Castañón-González J., Samaniego J.
Acta Biochimica Polonica
|
2014
|
vol. 61
|
issue 4
693-698
EN
The design of drugs with bioinformatics methods to identify proteins and peptides with a specific toxic action is increasingly recurrent. Here, we identify toxic proteins towards the influenza A virus subtype H1N1 located at the UniProt database. Our quantitative structure-activity relationship (QSAR) approach is based on the analysis of the linear peptide sequence with the so-called Polarity Index Method that shows an efficiency of 90% for proteins from the Uniprot Database. This method was exhaustively verified with the APD2, CPPsite, Uniprot, and AmyPDB databases as well as with the set of antibacterial peptides studied by del Rio et al. and Oldfield et al.
3
Content available remote

Computational model of abiogenic amino acid condensation to obtain a polar amino acid profile

88%
Polanco C., Buhse T., Samaniego J., Castañón González J., Estrada M.
Acta Biochimica Polonica
|
2014
|
vol. 61
|
issue 2
253-258
EN
In accordance with the second law of thermodynamics, the Universe as a whole tends to higher entropy. However, the sequence of far-from-equilibrium events that led to the emergence of life on Earth could have imposed order and complexity during the course of chemical reactions in the so-called primordial soup of life. Hence, we may expect to find characteristic profiles or biases in the prebiotic product mixtures, as for instance among the first amino acids. Seeking to shed light on this hypothesis, we have designed a high performance computer program that simulates the spontaneous formation of the amino acid monomers in closed environments. The program was designed in reference to a prebiotic scenario proposed by Sydney W. Fox. The amino acid abundances and their polarities as the two principal biases were also taken into consideration. We regarded the computational model as exhaustive since 200 000 amino acid dimers were formed by simulation, subsequently expressed in a vector and compared with the corresponding amino acid dimers that were experimentally obtained by Fox. We found a very high similarity between the experimental results and our simulations.
4
Content available remote

Characterization of a possible uptake mechanism of selective antibacterial peptides

88%
Polanco C., Samaniego J., Castañón-González J., Buhse T., Sordo M.
Acta Biochimica Polonica
|
2013
|
vol. 60
|
issue 4
629-633
EN
Selective antibacterial peptides containing less than 30 amino acid residues, cationic, with amphipathic properties, have been the subject of several studies due to their active participation and beneficial effects in strengthening the immune system of all living organisms. This manuscript reports the results of a comparison between the group of selective antibacterial peptides and another group called "cell penetrating peptides". An important number of the selective antibacterial peptides are cell penetrating peptides, suggesting that their toxicity is related to their uptake mechanism. The verification of this observation also includes the adaptation of a method previously published, called Polarity index, which reproduces and confirms the action of this new set of peptides. The efficiency of this method was verified based on four different databases, yielding a high score. The verification was based exclusively on the peptides already reported in the databases which have been experimentally verified.
5
Publication available in full text mode
Content available

Identification of proteins associated with Mycobacterium tuberculosis virulence pathway by their polar profile

76%
Polanco C., Castañón-González J., Mancilla R., Buhse T., Samaniego J., Gimbel A.
|
|
issue 2
191-196
EN
With almost one third of the world population infected, tuberculosis is one of the most devastating diseases worldwide and it is a major threat to any healthcare system. With the mathematical-computational method named "Polarity Index Method", already published by this group, we identified, with high accuracy (70%), proteins related to Mycobacterium tuberculosis bacteria virulence pathway from the Tuberculist Database. The test considered the totality of proteins cataloged in the main domains: fungi, bacteria, and viruses from three databases: Antimicrobial Peptide Database (APD2), Tuberculist Database, Uniprot Database, and four antigens of Mycobacterium tuberculosis: PstS-1, 38-kDa, 19-kDa, and H37Rv ORF. The method described was calibrated with each database to achieve the same performance, showing a high percentage of coincidence in the identification of proteins associated with Mycobacterium tuberculosis bacteria virulence pathway located in the Tuberculist Database, and identifying a polar pattern regardless of the group studied. This method has already been used in the identification of diverse groups of proteins and peptides, showing that it is an effective discriminant. Its metric considers only one physico-chemical property, i.e. polarity.
6
Content available remote

Identification of proteins associated with amyloidosis by polarity index method

52%
Polanco C., Samaniego J., Uversky V., Castañón-González J., Buhse T., Leopold-Sordo M., Madero-Arteaga A., Morales-Reyes A., Tavera-Sierra L., González-Bernal J., Arias-Estrada M.
|
|
issue 1
41-55
EN
There is a natural protein form, insoluble and resistant to proteolysis, adopted by many proteins independently of their amino acid sequences via specific misfolding-aggregation process. This dynamic process occurs in parallel with or as an alternative to physiologic folding, generating toxic protein aggregates that are deposited and accumulated in various organs and tissues. These proteinaceous deposits typically represent bundles of β-sheet-enriched fibrillar species known as the amyloid fibrils that are responsible for serious pathological conditions, including but not limited to neurodegenerative diseases, grouped under the term amyloidoses. The proteins that might adopt this fibrillar conformation are some globular proteins and natively unfolded (or intrinsically disordered) proteins. Our work shows that intrinsically disordered and intrinsically ordered proteins can be reliably identified, discriminated, and differentiated by analyzing their polarity profiles generated using a computational tool known as the polarity index method (Polanco & Samaniego, 2009; Polanco et al., 2012; 2013; 2013a; 2014; 2014a; 2014b; 2014c; 2014d). We also show that proteins expressed in neurons can be differentiated from proteins in these two groups based on their polarity profiles, and also that this computational tool can be used to identify proteins associated with amyloidoses. The efficiency of the proposed method is high (i.e. 70%) as evidenced by the analysis of peptides and proteins in the APD2 database (2012), AVPpred database (2013), and CPPsite database (2013), the set of selective antibacterial peptides from del Rio et al. (2001), the sets of natively unfolded and natively folded proteins from Oldfield et al. (2005), the set of human revised proteins expressed in neurons, and non-human revised proteins expressed in neurons, from the Uniprot database (2014), and also the set of amyloidogenic proteins from the AmyPDB database (2014).
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.