Environmental Risk Assessment Studies of Heavy Metal Contamination in the Industrial Area of Kattedan,India—A Case Study

Kattedan is an industrial area near Hyderabad, Andhra Pradesh, India, contaminated with high concentrations of metals attributed to industrial sources (battery manufacturing, metal plating, textile and pharmaceuticals production and others). Twelve different locations in the Kattedan industrial area were assessed for concentrations of metals (Zn, Cr, Cu, Ni, Co, Pb, Hg, Cd, and As) in soils, waters, and vegetation. Application of sequential extraction technique for the soils revealed relatively high percentages of Zn, Cu, and Cr associated with mobile fractions, and correspondingly high concentrations of Zn, Cr, Cu, and Pb in forage grass samples and a high degree of bioavailability to humans. Human exposure assessment revealed high concentrations of Pb, Zn, and Cr in blood and urine samples from the residents of the study area showing a direct pathway and a potential for toxicological hazard due to heavy metal pollution.     

Isolation and partial characterization of collagen from outer skin of Sepia pharaonis (Ehrenberg, 1831) from Puducherry coast

Type I collagen from outer skin of Sepia pharaonis was extracted and partially characterized. Yield of Acid Soluble Collagen (ASC) and Pepsin Soluble Collagen (PSC) were calculated as 1.66% and 3.93% and the total protein content of ASC and PSC were found as 18.4% and 48.6%. FT-IR spectrum of ASC and PSC recorded 12 and 14 peaks, respectively. ¹H NMR spectrum of ASC showed singlets at 1.23 ppm, 3.1 ppm, 3.55 ppm and 3.7 ppm and PSC at 1.23 ppm and 2.08 ppm. The molecular weight for ASC was calculated as 102 kDa and for PSC as 110, 108 and 102 kDa through SDS-PAGE. Differential Scanning Calorimetry (DSC) results supported that PSC withstand high thermal stability (82.85 °C) than ASC (73.13 °C). Higher denaturation temperature with high molecular weight well support the property of type I collagen from skin of S. pharaonis and it could be used as another potent source for the extraction of collagen.     

Critical role of bicarbonate and bicarbonate transporters in cardiac function

Bicarbonate is one of the major anions in mammalian tissues and extracellular fluids. Along with accompanying H+, HCO3- is generated from CO2 and H2 O, either spontaneously or via the catalytic activity of carbonic anhydrase. It serves as a component of the major buffer system, thereby playing a critical role in pH homeostasis. Bicarbonate can also be utilized by a variety of ion transporters, often working in coupled systems, to transport other ions and organic substrates across cell membranes. The functions of HCO3- and HCO3--transporters in epithelial tissues have been studied extensively, but their functions in heart are less well understood. Here we review studies of the identities and physiological functions of Cl-/HCO3- exchangers and Na+/HCO3-cotransporters of the SLC4 A and SLC26 A families in heart. We also present RNA Seq analysis of their cardiac mRNA expression levels. These studies indicate that slc4a3(AE3) is the major Cl-/HCO3- exchanger and plays a protective role in heart failure, and that Slc4a4(NBCe1) is the major Na+/HCO3- cotransporter and affects action potential duration. In addition, previous studies show that HCO3- has a positive inotropic effect in the perfused heart that is largely independent of effects on intracellular Ca2+. The importance of HCO3- in the regulation of contractility is supported by experiments showing that isolated cardiomyocytes exhibit sharply enhanced contractility, with no change in Ca2+ transients, when switched from Hepes-buffered to HCO3-- buffered solutions. These studies demonstrate that HCO3- and HCO3--handling proteins play important roles in the regulation of cardiac function.     

Effect of H4R antagonist N-(2-aminoethyl)-5-chloro-1H-indol-2-carboxamides and 5-chloro-2-(piperazin-1-ylmethyl)-1H-benzimidazole on histamine and 4-methylhistamine-induced mast cell response

Context: The histamine plays a decisive role in acute and chronic inflammatory responses and is regulated through its four types of distinct receptors designated from H1 to H4. Recently histamine 4 receptor (H4R) antagonists have been reported to possess various pharmacological effects against various allergic diseases.

Objective: To investigate the inhibitory effect of N-(2-aminoethyl)-5-chloro-1H-indol-2-carboxamide (Compound A) and 5-chloro-2-(piperazin-1-ylmethyl)-1H-benzimidazole (Compound L) on H4R-mediated calcium mobilization, cytokine IL-13 production, ERK1/2, Akt and NF-κB activation in human mastocytoma cells-1 (HMC-1).

Materials and methods: Compounds A and L were synthesized chemically and their inhibitory effect on intracellular calcium release was analyzed by Fluo-4 calcium assay, cytokine measurement through ELISA and activation of signaling molecules by western blot.

Results: Pre-treatment with compounds A and L significantly reduced the H4R-mediated intracellular calcium release. Histamine and 4-methylhistamine (4-MH) induced Th2 cytokine IL-13 production in HMC-1 cells, was inhibited by compound A (77.61%, 74.25% at 1?μM concentration) and compound L (79.63%, 81.70% at 1?μM concentration). Furthermore, histamine induced the phosphorylation of ERK1/2, Akt and NF-κB was suppressed by compounds A and L at varying levels, ERK1/2 (88%, 86%), Akt (88%, 89%) and NF-κB (89%, 87%) in HMC-1 cells.

Discussion and conclusions: Taken together these data demonstrate that compound A and compound L may block H4R-mediated downstream signaling events.     

Channel-forming, self-assembling, bishelical amphiphilic peptides: design, synthesis and crystal structure of Py(Aibn)2, n=2,3,4.

The design, synthesis, characterization and self-assembling properties of a new class of amphiphilic peptides, constructed from a bifunctional polar core attached to totally hydrophobic arms, are presented. The first series of this class, represented by the general structure Py(Aibn)2 (Py=2,6-pyridine dicarbonyl unit; Aib=alpha, alpha'-dimethyl glycine; n=1-4), is prepared in a single step by the condensation of commercially available 2,6-pyridine dicarbonyl dichloride with the methyl ester of homo oligoAib peptide (Aibn-OMe) in the presence of triethyl amine. 1H NMR VT and ROESY studies indicated the presence of a common structural feature of 2-fold symmetry and an NH...N hydrogen bond for all the members. Whereas the Aib3 segment in Py(Aib3)2 showed only the onset of a 3(10)-helical structure, the presence of a well-formed 3(10)-helix in both Aib4 arms of Py(Aib4)2 was evident in the 1H NMR of the bispeptide. X-ray crystallographic studies have shown that in the solid state, whereas Py(Aib2)2 molecules organize into a sheet-like structure and Py(Aib3)2 molecules form a double-stranded string assembly, the tetra Aib bispeptide, Py(Aib4)2, is organized to form a tetrameric assembly which in turn extends into a continuous channel-like structure. The channel is totally hydrophobic in the interior and can selectively encapsulate lipophilic ester (CH3COOR, R=C2H5, C5H11) molecules, as shown by the crystal structures of the encapsulating channel. The crystal structure parameters are: 1b, Py(Aib2)2, C25H37N5O8, sp. gr. P2(1)2(1)2(1), a=9.170(1) A, b=16.215(2) A, c=20.091(3) A, R=4.80; 1c, Py(Aib3)2, C33H51N7O10H2O, sp. gr. P1, a=11.040(1) A, b=12.367(1) A, c=16.959(1) A, alpha =102.41 degrees, beta =97.29 degrees, gamma =110.83 degrees, R1=6.94; 1 da, Py(Aib4)2.et ac, C41H65N9O12.1.5H2O.C4H8O2, sp. gr. P1, a=16.064(4) A, b=16.156 A, c=21.655(5) A, alpha =90.14(1)degrees, beta=101.38(2) degrees, gamma=97.07(1)degrees, Z=4, R1=9.03; 1db, Py(Aib4)2.amylac, C41H65N9O12.H2O.C7H14O2, P2(1)/c, a=16.890(1) A, b=17.523(1)A, c=20.411(1) A, beta=98.18 degrees, Z=4, R=11.1 (with disorder).     

<Emphasis Type="Italic">Planococcus antarcticus</Emphasis> and<Emphasis Type="Italic"> Planococcus psychrophilus</Emphasis> spp. nov. isolated from cyanobacterial mat samples collected from ponds in Antarctica

Thirteen orange-pigmented bacteria associated with cyanobacterial mat samples collected from four different lakes in McMurdo, Antarctica, were isolated. Twelve of the isolates, which were coccoid in shape, were very similar and possessed all the characteristics of the genus Planococcus and represented a new species, which was assigned the name Planococcus antarcticus sp. nov. (CMS 26or(T)). Apart from the phenotypic differences, P. antarcticus differed from all reported species of Planococcus by more than 2.5% at the 16S rRNA gene sequence level. In addition, at the DNA-DNA hybridization level, it exhibited very little similarity either with P. mcmeekinii (30%-35%), P. okeanokoites (26%-29%), or CMS 53or(T) (15%-25%), the three species with which it is closely related at the rRNA gene sequence level (2.5%-2.9%). P. antarcticus also showed only 2.5% difference in its 16S rRNA gene sequence compared with the P. alkanoclasticus sequence. But it was distinctly different from P. alkanoclasticus, which exists only as rods, is mesophilic and phosphatase positive, can hydrolyze starch, cannot utilize succinate, glutamate, or glucose, and cannot acidify glucose. Most important, P. antarcticus and P. alkanoclasticus varied distinctly in their fatty acid composition in that C(15:0), C(15:1), C(16:0), iso-C(16:1), and C(17:0) were present only in P. antarcticus but absent in P. alkanoclasticus. CMS 53or(T), the thirteenth isolate, was also identified as a new species of Planococcus and was assigned the name Planococcus psychrophilus sp. nov. This species was distinctly different from all the reported species, including the new species P. antarcticus, with respect to a number of phenotypic characteristics. At the 16S rRNA gene sequence level, it was closely related to P. okeanokoites (98.1%) and P. mcmeekinii (98%), but with respect to the DNA-DNA hybridization, the similarity was only 35%-36%. The type strain of P. antarcticus is CMS 26or(T) (MTCC 3854; DSM 14505), and that of P. psychrophilus is CMS 530r(T) (MTCC 3812; DSM 14507).     

Tigerinins: novel antimicrobial peptides from the Indian frog Rana tigerina

Four broad-spectrum, 11 and 12 residue, novel antimicrobial peptides have been isolated from the adrenaline-stimulated skin secretions of the Indian frog Rana tigerina. Sequences of these peptides have been determined by automated Edman degradation, by mass spectral analysis and confirmed by chemical synthesis. These peptides, which we have named as tigerinins, are characterized by an intramolecular disulfide bridge between two cysteine residues forming a nonapeptide ring. This feature is not found in other amphibian peptides. Conformational analysis indicate that the peptides tend to form beta-turn structures. The peptides are cationic and exert their activity by permeabilizing bacterial membranes. Tigerinins represent the smallest, nonhelical, cationic antimicrobial peptides from amphibians.     

PHYSICOCHEMICAL CHARACTERISTICS AND ANTIOXIDANT EFFICACY OF CHITOSAN FROM THE INTERNAL SHELL OF SPINELESS CUTTLEFISH Sepiella inermis

Cuttlefish chitosan was extracted from the cuttlebone of Sepiella inermis by demineralization and deproteinization and produced by deacetylation, and its physical and chemical parameters were also compared with that of commercial chitosan. Ash, moisture, and mineral and metal content of the chitosan was estimated by adopting standard methodologies. The rate of deacetylation was calculated as 79.64% by potentiometric titration. Through viscometry and gel permeation chromatography, the molecular weight of chitosan was found to be significantly lower than that of the commercial chitosan. Optical activity was found to be levorotatory. The structure of the chitosan was elucidated with spectral techniques such as Fourier-transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy. Cuttlefish chitosan showed a melting endothermic peak at 117.32°C. The x-ray diffraction (XRD) pattern of chitosan and standard chitosan exhibited the same crystalline peaks. Through scanning electron microscopy (SEM) the fine structure of chitosan was studied. The binding capacity (water and fat) of cuttlefish chitosan was found to be significantly higher than that of the commercial chitosan. The antioxidant efficacy of chitosan was determined through the conjugated diene method, scavenging ability on DPPH radicals, reducing power, and chelating ability on ferrous ions. This study has brought out the importance of shell as a potential source for obtaining another natural antioxidant.     

Dictyostelium caveatum mutants selected for a nystatin-resistant phenotype are cross-resistant to pisatin and other isoflavonoid phytoalexins

Cellular slime mould amoebae can be induced to become resistant to an otherwise inhibitory concentration of pisatin, an isoflavonoid phytoalexin of pea, if they are first treated with a subinhibitory concentration. We report here the serendipitous isolation of pisatin-resistant mutants in the cellular slime mouldDictyostelium caveatum. However, the pisatin resistance phenotype of the mutants appears to have a different basis than the inducible pisatin resistance phenotype of the wild type.     

Signaling by the human serotonin1A receptor is impaired in cellular model of Smith-Lemli-Opitz Syndrome

The Smith-Lemli-Opitz Syndrome (SLOS) is a congenital and developmental malformation syndrome associated with defective cholesterol biosynthesis. SLOS is clinically diagnosed by reduced plasma levels of cholesterol along with elevated levels of 7-dehydrocholesterol (and its positional isomer 8-dehydrocholesterol) and the ratio of their concentrations to that of cholesterol. Since SLOS is associated with neurological deformities and malfunction, exploring the function of neuronal receptors and their interaction with membrane cholesterol under these conditions assumes significance. We have earlier shown the requirement of membrane cholesterol for the ligand binding function of an important neurotransmitter G-protein coupled receptor, the serotonin_1A receptor. In the present work, we have generated a cellular model of SLOS using CHO cells stably expressing the human serotonin_1A receptor. This was achieved by metabolically inhibiting the biosynthesis of cholesterol, utilizing a specific inhibitor (AY 9944) of the enzyme required in the final step of cholesterol biosynthesis. We utilized this cellular model to monitor the function of the human serotonin_1A receptor under SLOS-like condition. Our results show that ligand binding activity, G-protein coupling and downstream signaling of serotonin_1A receptors are impaired in SLOS-like condition, although the membrane receptor level does not exhibit any reduction. Importantly, metabolic replenishment of cholesterol using serum partially restored the ligand binding activity of the serotonin_1A receptor. These results are potentially useful in developing strategies for the future treatment of the disease since intake of dietary cholesterol is the only feasible treatment for SLOS patients.