Direct antimicrobial activities of PR-bombesin

PR-bombesin is a bombesin-like peptide derived from the skin of tile Chinese red belly toad, Bombina maxima. The 8-residue segment of N-terminal of RP-bombesin, comprising four prolines and three basic residues, is extensively different front other bombes

An immunoregulatory peptide from salivary glands of the horsefly, Hybomitra atriperoides

Horseflies are economically important blood-feeding arthropods and also a nuisance for humans, and vectors for filariasis. They rely heavily on the pharmacological propriety of their saliva to get blood meat and suppress immune reactions of hosts. Little information is available on horsefly immune suppressants. By high-performance liquid chromatography (HPLC) purification coupling with pharmacological testing, an immunoregulatory peptide named immunoregulin HA has been identified and characterized from salivary glands of the horsefly of Hybomitra atriperoides (Diptera, Tabanidae). Immunoregulin HA could inhibit the secretion of interferon-gamma (IFN-gamma) and monocyte chemoattractant protein (MCP-1) and increase the secretion of interteukin-10 (IL-10) induced by lipopolysaccharide (LIPS) in rat splenocytes. IL-10 is a suppressor cytokine of T-cell proliferative and cytokine responses. IL-10 can inhibit the elaboration of pro-inflammatory cytokines. Immunoregulin HA possibly unregulated the IL-10 production to inhibit IFN-gamma and MCP-1 secretion in the current experiments. This immunosuppression may facilitate the blood feeding of this horsefly. The current works will facilitate to understand the molecular mechanisms of the ectoparasite-host relationship. 2008 Elsevier Ltd. All rights reserved.

Characterization of a thrombin-like enzyme from the venom of Trimeresurus jerdonii

From the venom of Trimeresurus jerdonii, a distinct thrombin-like enzyme, called jerdonobin. was purified by DEAF A-25 ion-exchange chromatography, Sephadex G-75 gel filtration, and fast protein liquid chromatography (FPLC). SDS-PAGE analysis of this enzyme shows that it consists of a single polypeptide chain with a molecular weight of 38,000. The NH2-terminal amino acid sequence of jerdonobin has great homology with venom thrombin-like enzymes documented. Jerdonobin is able to hydrolyze several chromogenic substrates. The enzyme directly clots fibrinogen with an activity of 217 NIH units/mg, The fibrinopeptides released, identified by HPLC consisted of fibrinopeptide A and a small amount of fibrinopepide B. The activities of the enzyme were inhibited by phenylmethylsulfonyl fluoride (PMSF) and p-nitrophenyl-p-guanidinobenzoate (NPGB). However, metal chelator (EDTA) had no effect on it. indicating it is venom serine protease. (C) 2000 Elsevier Science Ltd. All rights reserved.

Actions of two serine proteases from Trimeresurus jerdonii venom on chromogenic substrates and fibrinogen

Jerdonobin and jerdofibrase are two serine proteases purified from the venom of Trimeresurus jerdonii. The Michaelis constant K-m and the catalytic rate constant K-cat of jerdonobin or jerdofibrase on three chromogenic substrates, H-D-Pro-Phe-Arg-pNA (S2302), H-D-Phe-pipecolyl-Arg-pNA (S2238), and H-D-Val-Leu-Lys-pNA (S2251) were obtained from lineweaver-Burk plots. Jerdofibrase could hydrolyze all three substrates, but jerdonobin had no detectable activity on S2251, suggesting a relatively broader substrate specificity for jerdofibrase than jerdonobin. By SDS-PAGE, jerdofibrase preferentially degraded Bbeta-chain of fibrinogen. It also degraded Aalpha-chain of fibrinogen with relatively slow activity, but did not act on the gamma-chain. In contrast, jerdonobin did not degrade fibrinogen within 12 h. Fibrinopeptides liberation test, identified by HPLC, showed jerdonobin released fibrinopeptide A and a small amount of fibrinopeptide B. Unlike jerdonobin, jerdofibrase mainly released fibrinopeptide B. These results indicate that the two enzymes differ in their ability to hydrolyze chromogenic substrates and in their actions on fibrinogen. (C) 2002 Elsevier Science Inc. All rights reserved.

Biochemical and biological properties of Trimeresurus jerdonii venom and characterization of a platelet aggregation-inhibiting acidic phospholipase A(2)

Several biochemical and biological activities such as phospholipase A(2), arginine esterase, proteolytic, L-amino acid oxidase, 5'nucleotidase, acetylcholinesterase, thrombin-like, anticoagulant, and hemorrhagic activities were determined for whole desiccated venom of Trimeresurus jerdonii. An acidic phospholipase (named TJ-PLA(2)) was purified by anionic exchange chromatography, gel filtration, and reverse phase HPLC. TJ-PLA(2) had a molecular weight of 16,000 and a pI of 4.8. TJ-PLA(2) was non-lethal to mice up to an i.p. dose of 15 mg/kg body weight and lacked neurotoxicity and myotoxicity. It induced edema in the footpads of mice. The purified enzyme inhibited ADP- and collagen-induced human platelet aggregation in a manner which was both dose- and time-dependent.

N49 phospholipase A(2), a unique subgroup of snake venom group II phospholipase A(2)

A novel phospholipase A(2) (PLA(2)) with Asn at its site 49 was purified from the snake venom of Protobothrops mucrosquamatus by using SP-Sephadex C25, Superdex 75, Heparin-Sepharose (FF) and HPLC reverse-phage C-18 chromatography and designated as TM-N49

Liriomyza huidobrensis in Yunnan, China: current distribution and genetic structure of a recently established population

Liriomyza huidobrensis Blanchard (Diptera: Agromyzidae) is a very serious and economically important pest around the world. Liriomyza huidobrensis in China was first reported from Kunming of Yunnan province in 1993. We report here that this pest has recen

Some biocybernetic aspects in gene expression and regulatory control

In eucaryotes, gene expression and control is a complex nonlinear process, where there are many control mechanisms and ways, both physic, chemical and informational control. By the exploration from the angle of biocybernetics, the authors suggest that gene expression is a co-control process. In this process, physic, chemical and informational feedback controls are associated and influential each other, and are cross and co-functional. The physic, chemical and informational control ways composed an order non-linear feedback control system in eucaryotes.

On the origin of new genes in Drosophila

Several mechanisms have been proposed to account for the origination of new genes. Despite extensive case studies, the general principles governing this fundamental process are still unclear at the whole-genome level. Here, we unveil genome-wide patterns

De novo origination of a new protein-coding gene in Saccharomyces cerevisiae

Origination of new genes is an important mechanism generating genetic novelties during the evolution of an organism. Processes of creating new genes using preexisting genes as the raw materials are well characterized, such as exon shuffling, gene duplicat

Repetitive element-mediated recombination as a mechanism for new gene origination in Drosophila

Previous studies of repetitive elements (REs) have implicated a mechanistic role in generating new chimerical genes. Such examples are consistent with the classic model for exon shuffling, which relies on non-homologous recombination. However, recent data

A novel serine protease inhibitor from Bungarus fasciatus venom

By Sephadex G-50 gel filtration, cation-exchange CM-Sephadex C-25 chromatography and reversed phase high-performance liquid chromatography (HPLC), a novel serine protease inhibitor named bungaruskunin was purified and characterized from venom of Bungarus fasciatus. Its cDNA was also cloned from the cDNA library of B. fasciatus venomous glands. The predicted precursor is composed of 83 amino acid (aa) residues including a 24-aa signal peptide and a 59-aa mature bungaruskunin. Bungaruskunin showed maximal similarity (64%) with the predicted serine protease inhibitor blackelin deduced from the cDNA sequence of the red-bellied black snake Pseudechis porphyriacus. Bungaruskunin is a Kunitz protease inhibitor with a conserved Kunitz domain and could exert inhibitory activity against trypsin, chymotrypsin, and elastase. By screening the cDNA library, two new B chains of beta-bungarotoxin are also identified. The overall structures of bungaruskunin and beta -bungarotoxin B chains are similar; especially they have highly conserved signal peptide sequences. These findings strongly suggest that snake Kunitz/BPTI protease inhibitors and neurotoxic homologs may have originated from a common ancestor. (c) 2007 Elsevier Inc. All rights reserved.

Biogeochemical study of poly aromatic hydrocarbons (PAHs) and its physiological affection response in mudskipper (Boleophthalmus dussumieri) at coast of Khuzestan

Study on the biomarkers types to assess health status of marine ecosystems in environmental biomonitoring has an important value. Accordingly, accumulation of polycyclic aromatic hydrocarbons(PAHs) in sediment, water and tissues (liver and gill) of mudskipper(i.e. Boleophthalmus dussumieri) and some physiological responses like lysosomal membrane change performed on haemocytes, stability of red blood cell membrane and the Glutathione-S Transferase (GST) activity in the liver were measured in mudskipper. Samples were obtained from five sites along north western coast of the Persian Gulf (Khuzestan coast). Red blood cell membrane changes after different concentration of PAHs at different time was also studied to evaluate impact of PAHs compound on cell membrane. PAHs concentration was measured by HPLC method. The activity of GST enzyme was analysed by spectrophotometric method. Lysosomal membrane change was measured by NRR time method and stability of red blood cell membrane was evaluated by EOF test. Total PAH concentrations in the coastal sea water, the sediments, the liver and the gill tissues ranged between 0.80-18.34 μg/l, 113.50-3384.34 ng g-1 (dry weight), 3.99-46.64 ng g-1 dw and 3.11-17.76 ng g-1 dw, respectively. Highest PAHs pollution was found at Jafari while the lowest was detected at Bahrakan sampling sites. The lowest enzymatic activity was identified at Bahrakan (7.19 ± 1.541 nmol/mg protein/min), while the highest was recorded at Jafari (46.96 ± 7.877 nmol/mg protein/min). Comparative analysis of GST activity in the liver of mudskippers showed significant difference (p < 0.05) between the locations of Jafari and Bahrakan, and with other sites. Moreover, no significant difference was detected between the locations of Arvand, Zangi and Samayeli (p < 0.05). The mean RT was below 90 minutes in all sampling sites. Values of mean RT of the dye ranged from 34 (for the blood samples of mudskipper collected from Jafari site) to 78 minutes (for the blood samples of mudskipper collected from Bahrakan site). Spatial evaluation revealed the longest RT in fish from Bahrakan as compared with those from other sites. Preliminary results showed a significant difference (p < 0.05) among sampling sites except between Arvand and Zangi (p > 0.05). Osmotic fragility curves indicated that erythrocytes collected from mudskippers at Jafari were the most 009 fragile followed by Zangi> Arvand> Samayeli> and Bahrakan. The mean erythrocyte fragility was significantly higher at Jafari site (p < 0.05) when compared to other sites. Significant differences were found between the various sites (p < 0.05).The result indicated no significant differences between the control and treatments of mudskipper RBC exposed to field concentrations of PAHs (P>0.05). The results further indicated significant differences (P<0.05) between the control and treatments of mudskipper RBC exposed to acute. Potency Divisor concentrations. It is clear from the present result that chronic. Potency Divisor concentrations protect red cells against osmotic hemolysis. This study, however, showed that PAH concentrations in this region are not higher than the available standards. The findings showed that Lysosomal membrane destabilization, liver GST activities and fragility of red cell membrane are highly sensitive in the mudskipper, B. dussumieri. Thus, mudskipper perceived to be good sentinel organisms for PAH pollution monitoring. Sediment PAH concentrations were strongly correlated with biomarkers, indicating that PAH type pollutants were biologically available to fish. One of the possible risk assessment implications of this study is that biomarkers can be applied not only to characterize biological effects of pollution exposures, but also to determine the bioavailability of pollution in aquatic systems. The results also indicated that PAHs compound possess anti haemolytic property.

Venomics and biological analysis of Scatophagus argus argus (Spotted scat) venom isolated in Persian Gulf, extraction and purification of hemolytic protein

Green scat namely as Scatophagus argus argus is a venomous aquarium fish belonging to Scatophagidae family. It can induce painful wounds in injured hand with partial paralysis to whom that touch the spines. Dorsal and ventral rough spines contain cells that produce venom with toxic activities. According to unpublished data collected from local hospitals in southern coastal region of Iran, S. argus is reported as a venomous fish. Envenomation induces clinical symptoms such as local pain, partial paralysis, erythema and itching. In the present study green scat (spotted scat) was collected from Persian Gulf coastal waters. SDS-PAGE indicated 12 distinct bands in the venom ranged between 10-250 KDa. The crude venom had hemolytic activity on human erythrocytes (1%) with an LC100 (Lytic Concentration) of about 1.7 μg. The crude venom can release 813 μg proteins from 0.5% casein. Phospholipase C activity was recorded at 3.125 μg of total venom. Our findings showed that the edematic activity remained over 48 h after injection. The purification of the venom was done by HPLC and 30 peaks were obtained within 80 min but only one peak in 68 min retention time showed hemolytic activity at 90% acetonitril was isolated. The area percentage of the hemolytic protein showed that this hemolytic protein consist of 32 percent of total proteins and its molecular weight was 72 KDa in SDS_PAGE. The results demonstrated that crude venom extracted from Iranian coastal border has different toxic and enzymatic activities.

Determination of bioaccumulation and microscopic survey of LAS pollutant effect on the liver, kidney and gill tissues of Rutilus frisii kutum in Caspian sea

Linear alkylbenzene sulfonate (LAS) are widely used in detergent industry. Due to contaminants entering the water, and the effects of their accumulation in fish, LAS, has a great importance in environmental pollution. In the present study, accumulation of LAS and its histological effects on gill tissue, liver and kidney of Caspian kutum (Rutilus frisii kutum) were studied. Caspian kutum is the most important and most valuable teleosts of the Caspian Sea. Due to releasing Caspian Kutum in rivers and Anzali Lagoon and unlimited entry of wastewater to the aquatic ecosystem, research on the impact of LAS on Caspian kutum is important. In the present study, fish exposed to sublethal concentrations of LAS (0.58, 1.16 and 2.32 mg/l) for 192 hours. Control treatments with three replicates at 0, 24, 48, 72, 96 and 192 hours were done. For assessments of the histological effects of LAS, tissue sections prepared and by using Hematoxylin - Eosin were stained, then the prepared sections, examined by light microscopy. For determination of the bio accumulation of LAS, the soxhlet extraction and solid phase extraction was performed to determine the amount of LAS using HPLC with fluorescence detector. According to results average of bioconcentration factor and LAS concentrations in fish had reached stable levels after approximately 72 h and thus represented steady state BCF values in this species. The value of steady-state bio-concentration factor of total LAS was 33.96 L.Kg- 1 and for each of the homologous C10-n-LAS, C11-n-LAS, C12-n-LAS and C13-n- LAS were 3.84, 6.15, 8.58 and 15.57 L.Kg-1 respectively. According to the results obtained in gills exposed to LAS, histopathological alteration include hypertrophy, lifting of lamella epithelium, edema, clubbing of lamellae hyperplasia, lamellar fusion and aneurysm were seen. In liver tissue exposed to three concentrations of LAS, congestion and dilation of sinusoids, irregular-shaped nuclei and degeneration in the hepatocyte, vacuolar degeneration and necrosis were observed. In kidney exposed to three concentrations of LAS, reduction of the interstitial haematopoietic tissue, degeneration in the epithelial cells of renal tubule, tubular degeneration, necrosis, shrinkage and luminal occlusion were observed. According to the results the most alteration due to exposure to LAS was seen in the gill tissue. None of the control samples showed histological effects of LAS.