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The highly toxic and medically important scorpion Leiurus quinquestriatus is the most common scorpion species in Egypt and in some regions, is medically problematic for the local population. We stu...

The geographical distribution and diversity of the scorpion fauna of Egypt was examined based on a large collection covering most of the country and in view of recent revisionary systematics. Six ecologically distinct zoogeographical regions are targeted in a collection scheme. The ecological and historical biogeography of the present-day distribution of the scorpion fauna of Egypt is discussed.

Background: The medically important desert-horned or Egyptian sand viper (Cerastes cerastes) is one of the most familiar snakes of the great deserts of North Africa and the Middle East. It is a poisonous and widely distributed snake in Africa and inhabits the sandy deserts of Egypt. Male and female specimens of C. cerastes have been compared from different aspects. Results: Morphologically, tail length relative to snout-vent length was compared. Males significantly showed longer tails than do females. From the venom aspect, males showed a significant (p

Various bioactive peptides have been identified in scorpion venom, but there are many scorpion species whose venom has not been investigated. In this study, we characterized venom components of the North African scorpion, Buthacus leptochelys, by mass spectrometric analysis and evaluated their insect toxicity. This is the first report of chemical and biological characterization of the B. leptochelys venom. LC/MS analysis detected at least 148 components in the venom. We isolated four peptides that show insect toxicity (Bl-1, Bl-2, Bl-3, and Bl-4) through bioassay-guided HPLC fractionation. These toxins were found to be similar to scorpion &alpha, and &beta, toxins based on their N-terminal sequences. Among them, the complete primary structure of Bl-1 was determined by combination of Edman degradation and MS/MS analysis. Bl-1 is composed of 67 amino acid residues and crosslinked with four disulfide bonds. Since Bl-1 shares high sequence similarity with &alpha, like toxins, it is likely that it acts on Na+ channels of both insects and mammals.

The taxonomy and diversity of the scorpion fauna of Egypt was examined based on a large collection from most parts of the country and in view of recent revisionary systematics. We assessed the validity of listed records in light of new taxonomic findings and geographic distribution data and present a new list and an identification key to the scorpion fauna of Egypt consisting of 31 species, 18 of which were collected during this survey. Four species were not accepted for the list because no voucher material was available.

Scorpions use their venom to immobilize prey items and defend themselves against predators. Scorpion venom is a complex mixture composed of a wide array of substances such as salts, small molecules, peptides, and proteins. During analysis of the prey capture behavior of the scorpion Parabuthus leiosoma, we noticed that the scorpion stings the prey several successive stings in different specific regions. The stings started with ventral surface of the abdomen followed by thorax, shoulders and finally the head. This finding raised the possibility that the scorpion might use the venom with different composition in different contexts. To check this possibility, venom was collected as sequential drops (stings) by electrical stimulation (20 Volt) of the telson of the Parabuthus leiosoma. Protein content was determined by spectrophotometer using total protein KIT. The results showed marked variation of the total protein among the consecutive stings of each of the investigated scorpions. To go further, the protein profiles for all the collected stings were analyzed separately using 10% SDS-polyacrylamide electrophoresis (SDS-PAGE). Similarly, differences were observed among the stings, not only in the number of the protein bands, but also in the intensity of the bands. Thus, these results indicated that different venom components are unequally represented among consecutive stings supporting the venom-metering hypothesis.

Background Hepatitis C virus (HCV) is a major global health problem, causing chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. Development of well-tolerated regimens with high cure rates and fewer side effects is still much needed. Recently, natural antimicrobial peptides (AMPs) are attracting more attention as biological compounds and can be a good template to develop therapeutic agents, including antiviral agents against a variety of viruses. Various AMPs have been characterized from the venom of different venomous animals including scorpions. Methods The possible antiviral activities of crude venoms obtained from five Egyptian scorpion species (Leiurus quinquestriatus, Androctonus amoreuxi, A. australis, A. bicolor and Scorpio maurus palmatus) were evaluated by a cell culture method using Huh7.5 cells and the J6/JFH1-P47 strain of HCV. Time-of-addition experiments and inactivation of enzymatic activities of the venoms were carried out to determine the characteristics of the anti-HCV activities. Results S. maurus palmatus and A. australis venoms showed anti-HCV activities, with 50% inhibitory concentrations (IC50) being 6.3 ± 1.6 and 88.3 ± 5.8 μg/ml, respectively. S. maurus palmatus venom (30 μg/ml) impaired HCV infectivity in culture medium, but not inside the cells, through virocidal effect. The anti-HCV activity of this venom was not inhibited by a metalloprotease inhibitor or heating at 60°C. The antiviral activity was directed preferentially against HCV. Conclusions S. maurus palmatus venom is considered as a good natural source for characterization and development of novel anti-HCV agents targeting the entry step. To our knowledge, this is the first report describing antiviral activities of Egyptian scorpion venoms against HCV, and may open a new approach towards discovering antiviral compounds derived from scorpion venoms.