Unveiling the Protein Components of the Secretory-Venom Gland and Venom of the Scorpion Centruroides possanii (Buthidae) through Omic Technologies.

Centruroides possanii is a recently discovered species of "striped scorpion" found in Mexico. Certain species of Centruroides are known to be toxic to mammals, leading to numerous cases of human intoxications in the country. Venom components are thought to possess therapeutic potential and/or biotechnological applications. Hence, obtaining and analyzing the secretory gland transcriptome and venom proteome of C. possanii is relevant, and that is what is described in this communication. Since this is a newly described species, first, its LD50 to mice was determined and estimated to be 659 ng/g mouse weight. Using RNA extracted from this species and preparing their corresponding cDNA fragments, a transcriptome analysis was obtained on a Genome Analyzer (Illumina) using the 76-base pair-end sequencing protocol. Via high-throughput sequencing, 19,158,736 reads were obtained and ensembled in 835,204 sequences. Of them, 28,399 transcripts were annotated with Pfam. A total of 244 complete transcripts were identified in the transcriptome of C. possanii. Of these, 109 sequences showed identity to toxins that act on ion channels, 47 enzymes, 17 protease inhibitors (PINs), 11 defense peptides (HDPs), and 60 in other components. In addition, a sample of the soluble venom obtained from this scorpion was analyzed using an Orbitrap Velos apparatus, which allowed for identification by liquid chromatography followed by mass spectrometry (LC-MS/MS) of 70 peptides and proteins: 23 toxins, 27 enzymes, 6 PINs, 3 HDPs, and 11 other components. Until now, this work has the highest number of scorpion venom components identified through omics technologies. The main novel findings described here were analyzed in comparison with the known data from the literature, and this process permitted some new insights in this field.

Indolealkylamines in the venom of the scorpion Thorellius intrepidus.

Scorpions are a group of arthropods that strike fear in many people due to their severe medical symptoms, even death, caused by their venomous stings. Even so, not all scorpion species contain harmful venoms against humans but still have valuable bioactive molecules, which could be used in developing new pharmaceutical leads for treating important diseases. This work conducted a comprehensive analysis of the venom from the scorpion Thorellius intrepidus. The venom of T. intrepidus was separated by size exclusion chromatography, and four main fractions were obtained. Fraction IV (FIV) contained small molecules representing over 90% of the total absorbance at 280 nm. Analysis of fraction FIV by RP-HPLC indicated the presence of three main molecules (FIV.1, FIV.2, and FIV.3) with similar UV absorbance spectra profiles. The molecular masses of FIV.1, FIV.2, and FIV.3 were determined, resulting in 175.99, 190.07, and 218.16 Da, respectively. Further confirmation through 1H-NMR and 13C-NMR analyses revealed that these molecules were serotonin, N-methylserotonin, and bufotenidine. These intriguing compounds are speculated to play a pivotal role in self-defense and increasing venom toxicity and could also offer promising biotechnological applications as small bioactive molecules.

Antimicrobial Compounds from Skin Secretions of Species That Belong to the Bufonidae Family.

Skin secretions of toads are a complex mixture of molecules. The substances secreted comprise more than 80 different compounds that show diverse pharmacological activities. The compounds secreted through skin pores and parotid glands are of particular interest because they help toads to endure in habitats full of pathogenic microbes, i.e., bacteria, fungi, viruses, and protozoa, due to their content of components such as bufadienolides, alkaloids, and antimicrobial peptides. We carried out an extensive literature review of relevant articles published until November 2022 in ACS Publications, Google Scholar, PubMed, and ScienceDirect. It was centered on research addressing the biological characterization of the compounds identified in the species of genera Atelopus, Bufo, Duttaphrynus, Melanophryniscus, Peltopryne, Phrynoidis, Rhaebo, and Rhinella, with antibacterial, antifungal, antiviral, and antiparasitic activities; as well as studies performed with analogous compounds and skin secretions of toads that also showed these activities. This review shows that the compounds in the secretions of toads could be candidates for new drugs to treat infectious diseases or be used to develop new molecules with better properties from existing ones. Some compounds in this review showed activity against microorganisms of medical interest such as Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Coronavirus varieties, HIV, Trypanosoma cruzi, Leishmania chagasi, Plasmodium falciparum, and against different kinds of fungi that affect plants of economic interest.

Venom gland transcriptome from Heloderma horridum horridum by high-throughput sequencing.

Lizards of the Helodermatidae (Anguimorpha) family consist of at least two well recognized species: Heloderma horridum horridum and Heloderma suspectum suspectum. They contain specialized glands in their jaws that produce venomous secretions that causes envenoming symptoms to bitten animals. One way to study proteins from such secretions is by RNA-seq; a powerful molecular tool to characterize the transcriptome of such specialized gland, and its protein secretions. The total RNA from venom gland tissues of H. horridum horridum was extracted and a cDNA library was constructed and sequenced. Overall, 114,172 transcripts were found, and 199 were annotated based on sequence similarities to previously described peptides/proteins. Transcripts coding for putative exendins, defensins, natriuretics and serine protease inhibitors were the most highly expressed. Transcripts that code for several putative serine proteases, phospholipases, metalloproteases, lipases, L-amino oxidase and nucleases were also found. Some of the novel identified transcripts were translationally controlled tumor proteins, venom factors, vespryns, waprins, lectins, cystatins and serine protease inhibitors. All these new protein structures may contribute to a better understanding of the venomous secretions of the Helodermatidae family.

A new species of Centruroides (Scorpiones, Buthidae) from Colima, Mexico.

As part of an ongoing survey of scorpion diversity in Colima, Mexico, the isolated mountain Cerro Grande, part of the Biosphere Reserve Sierra de Manantlán, was investigated. Centruroides possanii sp. nov., the fifth species of the genus from the state, was discovered during fieldwork in the massif and is described in the present paper. Physiographical and climatic features of Cerro Grande may restrict the range of this new species; thus, we hypothesized that it may be a microendemic species that requires priority conservation. The new species is not assigned to any Centruroides species group recognized because some of its morphological features do not fit the current diagnosis of any of these groups, and these different groups are non-monophyletic and consequently ill-diagnosed. The new species is profusely illustrated, particularly the hemispermatophore. A distribution map is presented along with the other two more common species distributed in Colima. Because only indirect data on the potency of its venom is available, the medical importance of this new species described here is yet to be known.

[Assessment of five thrombophilic genetic polymorphisms among couples with habitual abortion]. / Evaluación de cinco polimorfismos de genes trombofílicos en parejas con aborto habitual.

An association between thrombophilic genes and obstetric conditions with early pregnancy termination has been previously proposed. In the present study we attempted to evaluate the possible association between thrombophilic genetic polymorphisms and habitual abortion (HA). Samples from two groups of volunteers were analyzed. The experimental group (n>100) was conformed by women attending the Centro Medico de Occidente, IMSS and their male couples, with a reproductive history ofat least three miscarriages. The reference group (n > 200) was composed by male and female healthy adults living in the state of Jalisco, Mexico. DNA was extracted from peripheral blood, and polymorphisms FII G20210A , FVG1691A, MTHFR C677T, ECA IID y TNF G-308A were typed by PCR-RFLP or -SSP. Genotype proportions in the reference group were in agreement with the HardyWeinberg expectations. Allele, genotype, and phenotype proportion inter-group comparisons did not show statistically significant differences. The present results could not demonstrate that thrombophilic polymorphisms constitute risk factors for HA in Jalisco.

Evaluación de cinco polimorfismos de genes trombofílicos en parejas con aborto habitual / Assessment of five thrombophilic genetic polymorphisms among couples with habitual abortion

Se han propuesto factores genéticos trombofílicos asociados con anormalidades obstétricas que implican la terminación temprana del embarazo. El propósito del estudio fue investigar la posible asociación de polimorfismos génicos trombofílicos con el aborto habitual (AH). Se analizaron muestras de dos grupos de personas que participaron voluntariamente en el estudio. El primero (n>100) consistió en mujeres atendidas en el Centro Médico de Occidente del Instituto Mexicano del Seguro Social y a sus parejas, por el antecedente reproductivo de por lo menos tres abortos idiopáticos (n>100). El grupo de referencia (n>200) lo formaron adultos sanos de ambos sexos residentes de Jalisco. El ADN se extrajo de una muestra de sangre periférica y se tipificaron, mediante PCR–RFLP o –SSP, los polimorfismos FII G20210A, FV G1691A, MTHFR C677T, ECA I/D y TNF G–308A. Las proporciones genotípicas en el grupo de referencia fueron similares a las predichas por la ley de Hardy–Weinberg y las comparaciones intergrupales alélicas, genotípicas y fenotípicas no mostraron diferencias significativas para ninguno de los polimorfismos estudiados. Estos resultados sugieren que los polimorfismos de los genes trombofílicos no representan un factor de riesgo para AH en nuestro medio.

An association between thrombophilic genes and obstetric conditions with early pregnancy termination has been previously proposed. In the present study we attempted to evaluate the possible association between thrombophilic genetic polymorphisms and habitual abortion (HA). Samples from two groups of volunteers were analyzed. The experimental group (n>100) was conformed by women attending the Centro Medico de Occidente, IMSS and their male couples, with a reproductive history ofat least three miscarriages. The reference group (n > 200) was composed by male and female healthy adults living in the state of Jalisco, Mexico. DNA was extracted from peripheral blood, and polymorphisms FII G20210A , FVG1691A, MTHFR C677T, ECA IID y TNF G-308A were typed by PCR-RFLP or -SSP. Genotype proportions in the reference group were in agreement with the HardyWeinberg expectations. Allele, genotype, and phenotype proportion inter-group comparisons did not show statistically significant differences. The present results could not demonstrate that thrombophilic polymorphisms constitute risk factors for HA in Jalisco.