Two new arthropod toxins purified from the venom of the Mexican scorpion Centruroides nigrescens

Posted by
  Two new arthropod toxins purified from the venom of the Mexican scorpion Centruroides nigrescens Abstract The venom of the slender black scorpion Centruroides nigrescens , from the State of Guerrero México, was fractionated by Sephadex G–50 gel filtration, followed by carboxymethyl cellulose ion separation and high–performance liquid chromatography, permitting to obtain two new peptides toxic to arthropods. The estimate LD 50 of the soluble venom for the insect Acheta domesticus was 11.1 μg/g body weight, and for the arthropod Armadillidium vulgare was 61.1 μg body weight . The amino acid sequence of toxin Cnige1 (toxic to A. domesticus and A. vulgare ) contains 65 amino acids, with a molecular mass of 7273.37 mass units, whereas toxin Cnige2, toxic to A. domesticus , contains 68 amino acids, with a molecular mass of 7548.81 units. Both peptides are well packed, containing 8 cysteines, which in the native venoms are forming 4 disulfide bridges each. The amino acid sequences f...

Antiviral action of different molecules obtained from invertebrates against coronavirus

Posted by

 

Antiviral action of different molecules obtained from invertebrates against coronavirus

Abstract

The few availability of antivirals for new strains of highly pathogenic viruses has become a serious public health problem that leads to the death of thousands of people annually. For this reason, the search for new products against these agents has become an urgent need. Many studies have been carried out with this aim. Among the multiple sources of research for new antibiotics and antivirals, bioprospecting for molecules obtained from invertebrates, or their products, has become an increasingly frequent option. Arthropods appeared on the planet around 350 million years ago and have been one of the beings with the greatest adaptability and resistance. Invertebrates have been found in all known ecosystems. Their survival for so long, in such different environments, is an indication that they have a very efficient protection system against environmental infections, despite not having a developed immune system like mammals. Historically, products obtained mainly from bees, such as honey and propolis, have been shown to be of great pharmacological importance, being used as antimicrobials, anti-inflammatory, antitumor, healing and several other functions. However, these molecules have also been obtained from other invertebrates, such as caterpillars and spiders. Previous studies by our group have demonstrated an intense antiviral and antimicrobial activity of these materials. In this study, we identified, isolated and characterized compounds with potent antiviral effect against avian Coronavirus in propolis from Scaptotrigona aff postica, hemolymph of Lonomia obliqua and from mygalin, an acylpolyamine, isolated from hemocytes of spider Acanthoscurria gomesiana. The antiviral assay was carried out by reducing infectious foci in cultures of infected cells and treated with these differents substances obtained from invertebrates. Propolis and crude hemolymph reduced avian coronavirus by an average of 256 x when used at a concentration of 5% v/v and an average reduction of 8x when 160 uM of Mygalin was used. Propolis purified and sinthetic hemolymph reduced the virus titer by an average 64 fold. The virus reduction with synthetic mygalin, at a concentration of 26 uM, was average of 16 times. The antiviral responses of the 3 substances were dose dependent. By the other hand, the virus titer reduction was 2 times more intense when the substances were added 1 hour before cell infection with the virus. The chemical characterization of the elements present in the extracts was carried out by liquid chromatography.

Antiviral action of different molecules obtained from invertebrates against coronavirus
Ronaldo Z Mendonca, Roberto M Nascimento, Ana C.O Fernandes, Maria I.P de Almeida, Pedro I.S Junior
bioRxiv 2024.01.04.574161; doi: https://doi.org/10.1101/2024.01.04.574161