In PLOS Pathogens, New York University microbiologist P'ng Loke and collaborators look at the consequences of using the parasitic whipworm Trichuris trichiura as a possible treatment for five rhesus macaque monkeys with idiopathic chronic diarrhea, or ICD, a condition that resembles ulcerative colitis. In four of the five animals, the helminth worm treatment seemingly improved ICD symptoms, they report. And array-based gene expression profiling, real-time PCR, and other analyses suggest that these improvements coincided with a dip in host inflammation in the gut. The study's authors also saw whipworm-related shifts in microbial communities clinging to the intestinal mucosa through their real-time PCR and sequencing-based analyses of bacterial 16S ribosomal RNA genes. "These findings suggest that helminth treatment in primates can ameliorate colitis by restoring mucosal barrier functions and reducing overall bacterial attachment," they say, "and also by altering the communities of attached bacteria."
A team from India's Assam University has used DNA barcoding to classify catfish caught at sampling sites across northern and eastern India at various times of year. As they report in PLOS One, the researchers sequenced bits of the cytochrome oxidase c subunit-I gene to generate barcode data for 75 catfish, which were also classified using traditional taxonomic approaches. Barcoding results indicated that 84 percent of the fish fell into 21 main species and highlighted range expansions for at least two of the catfish species. Four of the species were more difficult to delineate using molecular approaches, the researchers note, while three appeared to be mislabeled in existing sequence databases, according to the new data.
A team from the UK and Israel explores the proportion of expressed bdelloid rotifer genes that apparently originated in other organisms in PLOS Genetics study. The aqueous microinvertebrate Adineta ricciae is known for its ability to withstand and adapt to environmental stress, including very dry conditions, despite relying exclusively on asexual reproduction. Through transcript sequencing of pooled samples from hydrated or desiccated A. ricciae bdelloid rotifers, researchers estimate that some 8 percent to 9 percent of the tiny invertebrate's expressed genes have been snatched from bacteria, fungi, protists, and other nearby creatures via horizontal gene transfer. Many of these borrowed genes encode enzymes, hinting that they contribute to the bdelloid rotifer's biochemical repertoire.
For more on the study, check out a recent story from our sister publication GenomeWeb Daily News.