Diversity of astacin-like metalloproteases identified by transcriptomic analysis in Peruvian Loxosceles laeta spider venom and in vitro activity characterization.

Loxosceles spiders are found in almost all countries of South America. In Peru, Loxosceles laeta species is the main responsible for the accidents caused by poisonous animals, being known as "killer spiders", due to the large number of fatal accidents observed. Astacin-like metalloproteases, named LALPs (Loxosceles astacin-like metalloproteases) are highly expressed in Loxosceles spiders venom gland. These proteases may be involved in hemorrhage and venom spreading, being relevant to the envenoming proccess. Thus, the aim of this work was to analyze Peruvian L. laeta venom gland transcripts using bioinformatics tools, focusing on LALPs. A cDNA library from Peruvian L. laeta venom glands was constructed and sequenced by MiSeq (Illumina) sequencer. After assembly, the resulting sequences were annotated, seeking out for similarity with previously described LALPs. Nine possible LALPs isoforms from Peruvian L. laeta venom were identified and the results were validated by in silico and in vitro experiments. This study contributes to a better understanding of the molecular diversity of Loxosceles venom and provide insights about the action of LALPs.

Complete mitochondrial genome sequence of Myrmecophaga tridactyla from Brazilian Savanna.

Myrmecophaga tridactyla, popularly known as giant anteater, is a member of Xenarthra magnorder which is under the threat of extinction. Herein, we describe the complete mitochondrial genome of M. tridactyla. The circular DNA molecule is 16,546 bp long, contains 13 protein-coding genes, two rRNA genes, 22 tRNA genes, and a non-coding Control Region of 1110 bp. All protein-coding genes are on the heavy strand, except for Nd6. Ten of the 13 PCGs contained an ATG start codon.