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Genetic analysis of Vibrio parahaemolyticus O3:K6 strains that have been isolated in Mexico since 1998

CARLOS ABRAHAM GUERRERO RUIZ (2017, [Artículo])

Vibrio parahaemolyticus is an important human pathogen that has been isolated worldwide from clinical cases, most of which have been associated with seafood consumption. Environmental and clinical toxigenic strains of V. parahaemolyticus that were isolated in Mexico from 1998 to 2012, including those from the only outbreak that has been reported in this country, were characterized genetically to assess the presence of the O3:K6 pandemic clone, and their genetic relationship to strains that are related to the pandemic clonal complex (CC3). Pathogenic tdh+ and tdh+/trh+ strains were analyzed by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Also, the entire genome of a Mexican O3:K6 strain was sequenced. Most of the strains were tdh/ORF8-positive and corresponded to the O3:K6 serotype. By PFGE and MLST, there was very close genetic relationship between ORF8/O3:K6 strains, and very high genetic diversities from non-pandemic strains. The genetic relationship is very close among O3:K6 strains that were isolated in Mexico and sequences that were available for strains in the CC3, based on the PubMLST database. The whole-genome sequence of CICESE-170 strain had high similarity with that of the reference RIMD 2210633 strain, and harbored 7 pathogenicity islands, including the 4 that denote O3:K6 pandemic strains. These results indicate that pandemic strains that have been isolated in Mexico show very close genetic relationship among them and with those isolated worldwide. © 2017 Guerrero et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Article, bacterial strain, biofouling, controlled study, Crassostrea, food intake, gene sequence, genetic analysis, genetic variability, Japan, Mexican, Mexico, molecular phylogeny, nonhuman, pandemic, pathogenicity island, sea food, serotyping, toxi BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA GENÉTICA GENÉTICA

Whole-genome comparison between reference sequences and oyster Vibrio vulnificus C-genotype strains

CARLOS ABRAHAM GUERRERO RUIZ (2019, [Artículo])

Whole-genome sequences of Vibrio vulnificus clinical genotype (C-genotype) from the CICESE Culture Collection, isolated from oysters, were compared with reference sequences of CMCP6 and YJ016 V. vulnificus C-genotype strains of clinical origin. The RAST web server estimated the whole genome to be ~4.8 Mb in CICESE strain 316 and ~4.7 Mb in CICESE strain 325. No plasmids were detected in the CICESE strains. Based on a phylogenetic tree that was constructed with the whole-genome results, we observed high similarity between the reference sequences and oyster C-genotype isolates and a sharp contrast with environmental genotype (E-genotype) reference sequences, indicating that the differences between the C- and E-genotypes do not necessarily correspond to their isolation origin. The CICESE strains share 3488 genes (63.2%) with the YJ016 strain and 3500 genes (63.9%) with the CMCP6 strain. A total of 237 pathogenicity associated genes were selected from reference clinical strains, where—92 genes were from CMCP6, 126 genes from YJ016, and 19 from MO6-24/ O; the presence or absence of these genes was recorded for the CICESE strains. Of the 92 genes that were selected for CMCP6, 67 were present in both CICESE strains, as were as 86 of the 126 YJ016 genes and 13 of the 19 MO6-24/O genes. The detection of elements that are related to virulence in CICESE strains—such as the RTX gene cluster, vvhA and vvpE, the type IV pili cluster, the XII genomic island, and the viuB genes, suggests that environmental isolates with the C-genotype, have significant potential for infection. © 2019 Guerrero et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Article, bacterial gene, bacterial strain, bacterial virulence, comparative study, controlled study, gene cluster, gene identification, genomic island, genotype, nonhuman, phylogenetic tree, sequence analysis, strain identification, Vibrio vulnificus BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA GENÉTICA GENÉTICA

COMPOSICIÓN FLORÍSTICA DE CUATRO HÁBITATS EN EL RANCHO LAS PAPAS DE ARRIBA, MUNICIPIO DE OJUELOS DE JALISCO, JALISCO, MÉXICO

Mollie Harker LUZ ADRIANA GARCIA RUBIO MONICA ELIZABETH RIOJAS LOPEZ (2008, [Artículo])

En el rancho Las Papas de Arriba, municipio de Ojuelos de Jalisco, Jalisco se estudió la composición florística y las formas biológicas de cuatro hábitats: matorral xerófilo crasicaule, pastizal, cultivo maduro de nopal tunero (Opuntia spp.) y cultivo joven de nopal tunero, con el objetivo de dar cuenta de la riqueza de este sitio y comparar la fisonomía de los diferentes ambientes. El catálogo consta de 356 especies y taxa subespecíficos, las que representan 73 familias y 230 géneros de plantas vasculares. Las familias con mayor número de géneros y especies son Asteraceae (48, 76), Poaceae (29, 46), Fabaceae (13, 19) y Cactaceae (6, 19) y los géneros con mayor riqueza Opuntia (10), Euphorbia (9), Solanum (7), Pseudognaphalium (6), Bouteloua (6), Ipomoea (6) y Muhlenbergia (6). Del total de especies registradas, 36% son endémicas de México y 4% son introducidas; nueve no se conocían antes de Jalisco y cinco tienen problemas de conservación. Las formas de vida mejor representadas son las plantas herbáceas con 285 especies, anuales 108 y perennes 177 (en conjunto alcanzando 80% del total). El matorral muestra la mayor diversidad alfa con 223 especies (62.6 % del total) y es el hábitat más complejo en fisonomía conteniendo siete formas de vida, así como el que presenta el mayor número de elementos exclusivos. El pastizal contiene 119 especies (33.4% del total), el cultivo maduro de nopal 138 (38.8%) y el cultivo joven de nopal 132 (37.1%). Estos dos últimos hábitats fueron los más similares en cuanto a la composición florística compartiendo 35% de las especies.

BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) BOTÁNICA GENERAL BOTÁNICA GENERAL