Project description:Antimicrobial resistance is a major threat to human health, hence there is an urgent need to discover antibacterial molecule(s). Previously, we hypothesized that microbial gut flora of animals are a potential source of antibacterial molecules. Among various animals, Cuora amboinensis (turtle) represents an important reptile species living in diverse ecological environments and feed on organic waste and terrestrial organisms and have been used in folk medicine. The purpose of this study was to mine turtle's gut bacteria for potential antibacterial molecule(s). Several bacteria were isolated from the turtle gut and their conditioned media were prepared. Conditioned media showed potent antibacterial activity against several Gram-positive (Bacillus cereus, Streptococcus pyogenes and methicillin-resistant Staphylococcus aureus) and Gram-negative (neuropathogenic Escherichia coli K1, Serratia marcescens, Pseudomonas aeruginosa, Salmonella enterica and Klebsiella pneumoniae) pathogenic bacteria. Conditioned media-mediated bactericidal activity was heat-resistant when treated at 95°C for 10?min. By measuring Lactate dehydrogenase release, the results showed that conditioned media had no effect on human cell viability. Tandem Mass Spectrometric analysis revealed the presence of various secondary metabolites, i.e., a series of known as well as novel N-acyl-homoserine lactones, several homologues of 4-hydroxy-2-alkylquinolines, and rhamnolipids, which are the signature metabolites of Pseudomonas species. These findings are significant and provide the basis for rational development of therapeutic interventions against bacterial infections.

| S-EPMC6861250 | biostudies-literature

Project description:The mitochondrial genome of Cuora mccordi

| PRJNA824477 | ENA

Morphological characterization and phylogenetic relationships of Indochinese box turtles-The <i>Cuora galbinifrons</i> complex.

Project description:The members of the Indochinese box turtle complex, namely Cuora galbinifrons, Cuora bourreti, and Cuora picturata, rank the most critically endangered turtle species on earth after more than three decades of over-harvesting for food, traditional Chinese medicine, and pet markets. Despite advances in molecular biology, species boundaries and phylogenetic relationships, the status of the C. galbinifrons complex remains unresolved due to the small number of specimens observed and collected in the field. In this study, we present analyses of morphologic characters as well as mitochondrial and nuclear DNA data to reconstruct the species boundaries and systematic relationships within the C. galbinifrons complex. Based on principal component analysis (PCA) and statistical analysis, we found that phenotypic traits partially overlapped among galbinifrons, bourreti, and picturata, and that galbinifrons and bourreti might be only subspecifically distinct. Moreover, we used the mitochondrial genome, COI, and nuclear gene Rag1 under the maximum likelihood criteria and Bayesian inference criteria to elucidate whether C. galbinifrons could be divided into three separate species or subspecies. We found strong support for a sister relationship between picturata and the other two species, and consequently, we recommend maintaining picturata as a full species, and classifying bourreti and galbinifrons as subspecies of C. galbinifrons. These findings provide evidence for a better understanding of the evolutionary histories of these critically endangered turtles.

| S-EPMC6912918 | biostudies-literature

Evolutionary distinctiveness of the extinct Yunnan box turtle (Cuora yunnanensis) revealed by DNA from an old museum specimen.

Project description:Cuora yunnanensis is an extinct turtle known from 12 specimens collected from Yunnan, China, before 1908. We used ancient DNA methods to sequence 1723 base pairs of mitochondrial DNA from a museum specimen of C. yunnanensis. Unlike some rare 'species' recently described from the pet trade, C. yunnanensis represents a lineage that is distinct from other known turtles. Besides C. yunnanensis, two other valid species (C. mccordi, C. zhoui) are unknown in the wild but are supposedly from Yunnan. Intensive field surveys for surviving wild populations of these critically endangered species are urgently needed.

| S-EPMC1810102 | biostudies-literature

Divergent Patterns of Endogenous Small RNA Populations From Seed and Vegetative Tissues of Glycine max

Project description:An overview of small RNAs sequences existing in seed development and contrasted with vegetative tissues of the soybean

2012-10-09 | GSE36728 | GEO