ABSTRACT
Toxoplasma gondii invade host cells using a multi-step process that depends on the regulated secretion of adhesions. To identify key primary sequence features of adhesins in this parasite, we analyze the relative frequency of individual amino acids, their dipeptide frequencies, and the polarity, polarizability and Van der Waals volume of the individual amino acids by using cluster analysis. This method identified cysteine as a key amino acid in the Toxoplasma adhesin group. The best vector algorithm of non-concatenated features was for 2 attributes: the single amino acid relative frequency and the dipeptide frequency. Polarity, polarizability and Van der Waals volume were not good classificatory attributes. Single amino acid attributes clustered unambiguously 67 apicomplexan hypothetical adhesins. This algorithm was also useful for clustering hypothetical Toxoplasma target host receptors. All of the cluster performances had over 70% sensitivity and 80% specificity. Compositional aminoacid data can be useful for improving machine learning-based prediction software when homology and structural data are not sufficient.
ABSTRACT
Teniendo en cuenta la vital importancia de la morfología y nomenclatura dental para estudios sistemáticos (evolución y clasificación) en mamíferos, y dada la escasa disponibilidad libre de fuentes bibliográficas comprensivas y actualizadas sobre este tema, se realizó está revisión con la intención de que la misma se convierta en un manual básico para cursos de mastozoología y zoología de vertebrados en nuestro medio. Además, una revisión como la aquí presentada, ayuda a construir puentes entre la biología y otras profesiones como la odontología, de cara a estudios paleontológicos, arqueológicos y forenses. Es por todo esto que se hace un breve repaso de las características distintivas de los mamíferos y se revisan los principales aspectos de su dentadura, como son su evolución, anatomía, nomenclatura y fórmulas dentarias, para con todo este bagaje sacar algunas conclusiones.
Taking into account the vital importance of the morphology and dental nomenclature for systematic studies in mammals (about evolution and classification), and given the limited availability of free bibliographic sources updated on this issue, we conducted this review with the aim that it can be a basic textbook for courses in mammalogy and vertebrate zoology. Furthermore, in order to design paleontological, archaeological and forensic studies, this review helps to make connections between biology and other professions such as dentistry. For these reasons we make a short revision of the distinguishing characteristics of mammals and review the main aspects about their teeth, such as their evolution, anatomy, nomenclature and dental formulas so that with all this background, some conclusions can be made.
