Promiscuous Domains in Eukaryotes and HAT Proteins in FUNGI Have Followed Different Evolutionary Paths.

Diverse studies have shown that the content of genes present in sequenced genomes does not seem to correlate with the complexity of the organisms. However, various studies have shown that organism complexity and the size of the proteome has, indeed, a significant correlation. This characteristic allows us to postulate that some molecular mechanisms have permitted a greater functional diversity to some proteins to increase their participation in developing organisms with higher complexity. Among those mechanisms, the domain promiscuity, defined as the ability of the domains to organize in combination with other distinct domains, is of great importance for the evolution of organisms. Previous works have analyzed the degree of domain promiscuity of the proteomes showing how it seems to have paralleled the evolution of eukaryotic organisms. The latter has motivated the present study, where we analyzed the domain promiscuity in a collection of 84 eukaryotic proteomes representative of all the taxonomy groups of the tree of life. Using a grammar definition approach, we determined the architecture of 1,223,227 proteins, conformed by 2,296,371 domains, which established 839,184 bigram types. The phylogenetic reconstructions based on differences in the content of information from measures of proteome promiscuity confirm that the evolution of the promiscuity of domains in eukaryotic organisms resembles the evolutionary history of the species. However, a close analysis of the PHD and RING domains, the most promiscuous domains found in fungi and functional components of chromatin remodeling enzymes and important expression regulators, suggests an evolution according to their function.

Phylogenomic study and classification of mitochondrial DNA through virtual genomic fingerprints.

In the present study, we evaluated the ability of the Virtual Analysis Method for Phylogenomic fingerprint Estimation (VAMPhyRE) toolkit to classify human mitochondrial DNA (mtDNA) haplogroups. In total, 357 random mtDNA sequences were obtained from different haplogroups, based on the classification of PhyloTree. Additionally, we included a control group of five sequences (Pan paniscus, Pan troglodytes, Homo sapiens neanderthalensis, Yoruba15, and the revised Cambridge reference sequence). VAMPhyRE employs a virtual hybridization technique, using probes that specifically bind to their complementary sequences in the genome. We used 65,536 probes of 8 nucleotides to identify potential sites where hybridization occurs between the mtDNA and the specific probe, forming different heteroduplexes and thus, creating a unique and specific genomic fingerprint for each sequence. Genomic fingerprints were compared, and a table of distances was calculated to obtain a mitochondrial phylogenomic tree with the macrohaplogroups, L, N, M, and R, and their corresponding haplogroups, according to universal nomenclature. The results obtained suggest an accuracy of 97.25% for the distribution of the 357 mtDNA sequences in the four macrohaplogroups and their corresponding haplogroups when compared with other mtDNA classification tools that require reference sequences and do not offer an analysis based on an evolutionary approach. These data are available online at http://biomedbiotec.encb.ipn.mx/VAMPhyRE/.

Phylogeny, evolution, and potential ecological relationship of cytochrome CYP52 enzymes in Saccharomycetales yeasts.

Cytochrome P450s from the CYP52 family participate in the assimilation of alkanes and fatty acids in fungi. In this work, the evolutionary history of a set of orthologous and paralogous CYP52 proteins from Saccharomycetales yeasts was inferred. Further, the phenotypic assimilation profiles were related with the distribution of cytochrome CYP52 members among species. The maximum likelihood phylogeny of CYP52 inferred proteins reveled a frequent ancient and modern duplication and loss events that generated orthologous and paralogous groups. Phylogeny and assimilation profiles of alkanes and fatty acids showed a family expansion in yeast isolated from hydrophobic-rich environments. Docking analysis of deduced ancient CYP52 proteins suggests that the most ancient function was the oxidation of C4-C11 alkanes, while the oxidation of >10 carbon alkanes and fatty acids is a derived character. The ancient CYP52 paralogs displayed partial specialization and promiscuous interaction with hydrophobic substrates. Additionally, functional optimization was not evident. Changes in the interaction of ancient CYP52 with different alkanes and fatty acids could be associated with modifications in spatial orientations of the amino acid residues that comprise the active site. The extended family of CYP52 proteins is likely evolving toward functional specialization, and certain redundancy for substrates is being maintained.

First clinical isolate of Escherichia coli harboring mcr-1 gene in Mexico.

Our aim in this report was to describe the characteristics of the first clinical isolate of Escherichia coli (EC-PAG-733) harboring the mcr-1 gene found in Mexico. This isolate was obtained from a fecal sample from a young child with an oncological condition. We obtained the whole-genome sequence using next-generation sequencing and analyzed the sequence by bioinformatics tools. EC-PAG-733 was resistant to third- and fourth-generation cephalosporins and was susceptible to all carbapenems and amikacin; it was also resistant to ciprofloxacin, levofloxacin, gentamicin and colistin at a minimum inhibitory concentration (MIC) of 4 µg/mL. This isolate was classified as O11:H25-ST457. EC-PAG-733 harbored an ESBL type CTX-M-55 as well as several virulence factors that have been associated with Enteroaggregative Escherichia coli (EAEC). The mcr-1 gene was located within an IncI2 plasmid. The results of this whole genome shotgun project were deposited in DDBJ/ENA/GenBank under the accession number QKXE00000000.