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Manthey, J.

Publications and source records attributed to Manthey, J..

4 recordsLinked to original sources

Studying Pathogens Degrades BLAST-based Pathogen Identification

As synthetic biology becomes increasingly capable and accessible, it is likewise increasingly critical to be able to make accurate biosecurity determinations regarding the pathogenicity or toxicity of particular nucleic acid or amino acid sequences. At present, this is typically done using the BLAST algorithm to determine the best match with sequences in the NCBI databases. Neither BLAST nor the NCBI databases, however, are actually designed for biosafety determination. Critically, taxonomic errors or ambiguities in the NCBI databases can also cause errors in BLAST-based taxonomic categorization. With heavily studied taxa and frequently used biotechnology tools, even low frequency taxonomic categorization issues can lead to high rates of errors in biosecurity decision-making. Here we focus on the implications for false positives, finding that NCBI BLAST will now incorrectly categorize a number of commonly used biotechnology tool sequences as the pathogens or toxins with which they have been used. Paradoxically, this implies that problems are expected to be most acute for the pathogens and toxins of highest interest and the most widely used biotechnology tools. We thus conclude that biosecurity tools should shift away from BLAST against NCBI and towards new methods that are specifically tailored for biosafety purposes.

bioinformatics↗

De Novo Assembly of a Chromosome-Scale Reference Genome for the Northern Flicker Colaptes auratus

The northern flicker, Colaptes auratus, is a widely distributed North American woodpecker and a long-standing focal species for the study of ecology, behavior, phenotypic differentiation, and hybridization. We present here a highly contiguous de novo genome assembly of C. auratus, the first such assembly for the species and the first published chromosome-level assembly for woodpeckers (Picidae). The assembly was generated using a combination of short-read Chromium 10x and long-read PacBio sequencing, and further scaffolded with chromatin conformation capture (Hi-C) reads. The resulting genome assembly is 1.378 Gb in size, with a scaffold N50 of 43.948 Mb and a scaffold L50 of 11. This assembly contains 87.4 % - 91.7 % of genes present across four sets of universal single-copy orthologs found in tetrapods and birds. We annotated the assembly both for genes and repetitive content, identifying 18,745 genes and a prevalence of ~ 28.0 % repetitive elements. Lastly, we used four-fold degenerate sites from neutrally evolving genes to estimate a mutation rate for C. auratus, which we estimated to be 4.007 x 10-9 substitutions / site / year, about 1.5x times faster than an earlier mutation rate estimate of the family. The highly contiguous assembly and annotations we report will serve as a resource for future studies on the genomics of C. auratus and comparative evolution of woodpeckers.

genomics↗

Highly Distinguished Amino Acid Sequences of 2019-nCoV (Wuhan Coronavirus)

Using a method for pathogen screening in DNA synthesis orders, we have identified a number of amino acid sequences that distinguish 2019-nCoV (Wuhan Coronavirus) from all other known viruses in Coronaviridae. We find three main regions of unique sequence: two in the 1ab polyprotein QHO60603.1, one in surface glycoprotein QHO60594.1.

genetics↗

Recent secondary contacts, background selection and variable recombination rates shape genomic diversity in the model species Anolis carolinensis

Gaining a better understanding on how selection and neutral processes affect genomic diversity is essential to gain better insights into the mechanisms driving adaptation and speciation. However, the evolutionary processes affecting variation at a genomic scale have not been investigated in most vertebrate lineages. Previous studies have been limited to a small number of model species, mostly mammals, and no studies have investigated genomic variation in non avian reptiles. Here we present the first population genomics survey using whole genome re sequencing in the green anole (Anolis carolinensis). This species has emerged as a model for the study of genomic evolution in squamates. We quantified how demography, recombination and selection have led to the current genetic diversity of the green anole by using whole-genome resequencing of five genetic clusters covering the entire species range. The differentiation of green anoles populations is consistent with a northward expansion from South Florida followed by genetic isolation and subsequent gene flow among adjacent genetic clusters. Dispersal out-of-Florida was accompanied by a drastic population bottleneck followed by a rapid population expansion. This event was accompanied by male-biased dispersal and/or selective sweeps on the X chromosome. We show that the combined effect of background selection and recombination rates is the main contributor to the genomic landscape of differentiation in the anole genome. We further demonstrate that recombination rates are positively correlated with GC content at third codon position (GC3) and confirm the importance of biased gene conversion in shaping genome wide patterns of diversity in reptiles.

evolutionary biology↗