Characterization of a new bioactive peptide from Potamotrygon gr. orbignyi freshwater stingray venom

Abstract

Brazilian freshwater stingrays, Potamotrygon gr. orbigyni, are relatively common in the middle-western regions of Brazil, where they are considered an important public health threat. In order to identify some of their naturally occurring toxin peptides available in very low amounts, we combine analytical protocols such as reversed-phase high-performance liquid chromatography (RP-HPLC), followed by a biological microcirculatory screening and mass spectrometry analysis. Using this approach, one bioactive peptide was identified and characterized, and two analogues were synthesized. The natural peptide named Porflan has the primary structure ESIVRPPPVEAKVEETPE (MW 2006.09 Da) and has no similarity with any bioactive peptide or protein found in public data banks. Bioassay protocols characterized peptides as presenting potent activity in a microcirculatory environment. The primary sequences and bioassay results, including interactions with the membrane phospholipids, suggest that these toxins are a new class of fish toxins, directly involved in the inflammatory processes of a stingray sting.

Studies on pharmacological properties of mucus and sting venom of Potamotrygon cf. henlei

“…henlei collected in Tocantins, together with a general biochemical and biological characterization of the samples of venom and mucus studied are reported. To the best of our knowledge, there is only a couple of reports dealing with the experimental toxicity of Potamotrygon stingray venoms [14] and [17], the characterization of two peptides [29,30] and the presence of a protein with hyaluronidase activity [42]. The venom of P. cf.…”

“…This work leads us to a better and more detailed study of this venom and its compounds, purifying toxins to allow pharmacological investigations. By this approach, we isolated two bioactive peptides from the venom of the P. gr orbignyi freshwater stingray [29,30]. These peptides, called orpotrin and porflan, shown to be effective in the microcirculatory environment, induce strong vasoconstriction and inflammation, respectively.…”

Fibrinogenolytic and anticoagulant activities in the tissue covering the stingers of marine stingrays Dasyatis sephen and Aetobatis narinari

“…Recently, vasoconstrictor and microcirculatory active peptide were isolated from Potomotrygon gr. orbignyi venom [10,11].…”

Antimicrobial and anticoagulant activities of the spine of stingray Himantura imbricata

“…Screening of antibacterial drugs from marine gastropod Chicoreus ramosus has also been done most recently by Ramasamy et al [20] . Stingray venom is a potential source of novel bioactive peptide like Orpotrin and Porflan [21] . Prabhu et al (2013) demonstrated the crude and fractions of starfish Stellaster equestris have remarkable antimicrobial activities against human bacterial pathogens [22] .…”