Venomous mammals are rare, and only a few species in the orders Insectivora and Monotremata produce toxic venom. Among them, the duckbill platypus (Ornithorhynchus anatinus) is one of the two venomous Australian mammals. The adult male platypus carries a spur on each hind leg, which it uses to inject competitors with poison. However, the structure and function of the poison's active compounds are still imcompletely characterized. We found that crude platypus venom produced potent Ca2+ influx in human neuroblastoma IMR-32 cells. Guided by this assay, we identified 11 unique peptides, including peptide H--His--Asp--His--Pro--Asn--Pro--Arg--OH, which coincided with the N-terminal domain residues of Ornithorhynchus venom C-type natriuretic peptide (OvCNP). This heptapeptide induced a significant increase in [Ca2+]I in IMR-32 cells at 75 Ã¼M; had relatively specific affinities for glutamate, histamine, and GABAA receptors; and facilitated neurogenic twitching in guinea pig ileum specimens at 30 Ã¼M. We also established that its proteinous venom fraction strongly hydrolyzed Pro--Phe--Arg--MCA and cleaved a human low-molecularweight kininogen (LK), similar to porcine pancreas kallikrein. These results strongly indicated that platypus venom contains tissue kallikrein-like protease(s), and its proteolytic activity might synergistically contribute to toxicity through the specific cleavage of other venom constituents.

The Devil is in the Details. Millar, Jocelyn // Journal of Chemical Ecology;Jun2014, Vol. 40 Issue 6, p517 The author opines on the superficially drafted chemical ecology research papers. Topics discussed include lack of proper methodology to identify compounds through mass spectrometry and no efforts done by scientists to match the given compound's isomers with the data present in the mass...

LC/MS Guided Isolation of Alkaloids from Lotus Leaves by pH-Zone-Refining Counter-Current Chromatography. Xia Xu; Cui-Rong Sun; Xiao-Jing Dai; Rui-Lin Hu; Yuan-Jiang Pan; Zhang-Fa Yang // Molecules;Mar2011, Vol. 16 Issue 3, p2551 The traditional methods used in natural product separation primarily target the major components and the minor components may thus be lost during the separation procedure. Consequently, it's necessary to develop efficient methods for the preparative separation and purification of relatively...

Anticonvulsant Effects of Fractions Isolated from Dinoponera quadriceps (Kempt) Ant Venom (Formicidae: Ponerinae). Morais Ferreira Nôga, Diana Aline; Mateus Brandão, Luiz Eduardo; Cagni, Fernanda Carvalho; Silva, Delano; de Azevedo, Dina Lilia Oliveira; Araújo, Arrilton; dos Santos, Wagner Ferreira; Miranda, Antonio; da Silva, Regina Helena; Ribeiro, Alessandra Mussi // Toxins;Jan2017, Vol. 9 Issue 1, p5 Natural products, sources of new pharmacological substances, have large chemical diversity and architectural complexity. In this context, some toxins obtained from invertebrate venoms have anticonvulsant effects. Epilepsy is a neurological disorder that affects about 65 million people worldwide,...

The Red Seaweed Gracilaria gracilis as a Multi Products Source. Francavilla, Matteo; Franchi, Massimo; Monteleone, Massimo; Caroppo, Carmela // Marine Drugs;Oct2013, Vol. 11 Issue 10, p3754 In recent years seaweeds have increasingly attracted interest in the search for new drugs and have been shown to be a primary source of bioactive natural compounds and biomaterials. In the present investigation, the biochemical composition of the red seaweed Gracilaria gracilis, collected...

Systematic isolation of microbial metabolites for natural products depository (NPDepo). Osada, Hiroyuki; Nogawa, Toshihiko // Pure & Applied Chemistry;Jun2012, Vol. 84 Issue 6, p1407 A microbial fraction library has been constructed as a part of RIKEN Natural Products Depository (NPDepo) to discover and isolate novel metabolites with unique biological activity from microbial sources efficiently and rapidly. The fraction library was made by a systematic separation method...

Investigating the thermal stability of six caffeoylquinic acids employing rapid-resolution liquid chromatography with quadrupole time-of-flight tandem mass spectrometry. Li, Yan-Jing; Zhang, Chen-Feng; Ding, Gang; Huang, Wen-Zhe; Wang, Zhen-Zhong; Bi, Yu-An; Xiao, Wei // European Food Research & Technology;Jun2015, Vol. 240 Issue 6, p1225 The caffeoylquinic acids (CQAs) are one important group with various biological activities of natural products in herbal medicines and food plants. This finding caused new interest in the properties and thermal stability of CQAs, since many processing and preparation of pharmaceutical and...

Informatic search strategies to discover analogues and variants of natural product archetypes. Johnston, Chad; Connaty, Alex; Skinnider, Michael; Li, Yong; Grunwald, Alyssa; Wyatt, Morgan; Kerr, Russell; Magarvey, Nathan // Journal of Industrial Microbiology & Biotechnology;Mar2016, Vol. 43 Issue 2/3, p293 Natural products are a crucial source of antimicrobial agents, but reliance on low-resolution bioactivity-guided approaches has led to diminishing interest in discovery programmes. Here, we demonstrate that two in-house automated informatic platforms can be used to target classes of biologically...

Genetic and Ecological Correlates of Intraspecific Variation in Pitviper Venom Composition Detected Using Matrix-Assisted Laser Desorption Time-of-Flight Mass Spectrometry (MALDI-TOF-MS) and Isoelectric Focusing. Creer, Simon; Malhotra, Anita; Thorpe, Roger S.; Stöcklin, Reto S.; Favreau, Philippe S.; Hao Chou, Wen S. // Journal of Molecular Evolution;Mar2003, Vol. 56 Issue 3, p317 The ability to detect biochemical diversity in animal venoms has wide-ranging implications for a diverse array of scientific disciplines. Matrix-assisted laser desorption time-of-flight mass spectrometry (and, for comparative purposes, isoelectric focusing) were used to characterize venoms from...