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Disulfide bond - Wikipedia, the free encyclopedia Disulfide bonds play an important protective role for bacteria as a reversible switch that turns a protein on or off when bacterial cells are exposed to oxidation reactions. In eukaryotic cells, disulfide bonds are formed in the lumen of the RER (rough endoplasmic reticulum) but not in the cytosol. It is breaking and remaking of the disulfide bonds which is the basis for the permanent wave. en.wikipedia.org /wiki/Disulfide_bond   (455 words)

Disulfide - Wikipedia, the free encyclopedia In chemistry, a disulfide ion is an anion (negatively-charged ion) formed by two sulfur atoms having an overall -2 charge. In many cases, each of the two sulfur atoms in a disulfide group is covalently bonded to a carbon atom in an organic compound, forming a disulfide bond, sometimes called a disulfide linkage or a disulfide bridge. The compound carbon disulfide (CS) has a covalently bonded molecule similar to carbon dioxide except both oxygen atoms are replaced by sulfur atoms. en.wikipedia.org /wiki/Disulfide   (263 words)

Carbon Disulfide - NSC   (Site not responding. Last check: 2007-10-10) Carbon disulfide is regulated by the Occupational Safety and Health Administration (OSHA), which sets permissible exposure limits for air (20 ppm C 30 ppm 100 ppm (30-minute maximum peak) of 4 ppm) for time-weighted average; and 12 ppm (36 mg/m3) for short-term exposure limit. Carbon disulfide is regulated by EPA under the Clean Air Act, which has requirements to prevent equipment leaks of volatile organic compounds in the synthetic organic chemical manufacturing industry. In 1998, 114,799,217 pounds of carbon disulfide waste were managed; 30,024,800 pounds were recycled on-site; 1,985 pounds were recycled off-site; 10,070,374 pounds were used for energy recovery on-site; 242,037 pounds were used for energy recovery off-site; 30,950,014 pounds were treated on-site; 253,664 pounds were treated off-site; and 43,256,343 pounds were released on-and off-site. www.nsc.org /library/chemical/carbondi.htm   (1379 words)

Permanent Hair Wave The formation of disulfide bonds has a direct application in producing curls in hair by the permanent wave process. The alpha-helices are extensively cross-linked with disulfide bonds from cysteine. Disulfide bonds are formed by oxidation of the sulfhydryl groups on cysteine. www.elmhurst.edu /~chm/vchembook/568hairwave.html   (376 words)

HHMI Lab Safety: LCSS: CARBON DISULFIDE   (Site not responding. Last check: 2007-10-10) Carbon disulfide is only slightly toxic to laboratory animals by inhalation or ingestion, but its toxicity is relatively greater in humans. Carbon disulfide should be handled in the laboratory using the "basic prudent practices" described in Chapter 5.C, supplemented by additional precautions for dealing with extremely flammable substances (Chapter 5.F). In particular, carbon disulfide should be used only in areas free of ignition sources (including hot plates, incandescent lightbulbs, and steam baths), and this substance should be stored in tightly sealed metal containers in areas separate from oxidizers. www.hhmi.org /about/labsafe/lcss/lcss19.html   (667 words)

ATSDR - ToxFAQs™: Carbon Disulfide The impure carbon disulfide that is usually used in most industrial processes is a yellowish liquid with an unpleasant odor, like that of rotting radishes. In nature, small amounts of carbon disulfide are found in gases released to the earth’s surface as, for example, in volcanic eruptions or over marshes. Carbon disulfide does not appear to be taken up in significant amounts by the organisms living in water. www.atsdr.cdc.gov /tfacts82.html   (992 words)

Carbon disulfide (EHC 10, 1979) Ten to 30% of absorbed carbon disulfide is exhaled, less than 1% is excreted in the urine, and the remaining 70-90% undergoes biotransformation before excretion in the urine in the form of metabolites. The carbon disulfide, which is absorbed by activated carbon in the tube, is later desorbed by a solvent and determined by gas chromatography (section 2.2.3). Furthermore, studies showing interactions between carbon disulfide and, tissue respiration; depression of cytochrome oxidase, succinic dehydrogenase, alkaline phosphatase, and dopamine-ß-hydroxylase; and influence of inhibitors of serum elastase (EC 3.4.21.11), suggest that besides a purely vascular etiology, it is plausible to consider a direct toxic interference of carbon disulfide with tissue metabolism (section 5.2). www.inchem.org /documents/ehc/ehc/ehc010.htm   (16648 words)

Carbon Disulfide (CICADS 46, 2002) Carbon disulfide (at the micrograms per litre or micrograms per cubic metre level) and its metabolite TTCA were detected in virtually all samples of breath, blood, urine, and breast milk of subjects with no known occupational exposure in a number of studies (Pellizzari et al., 1982; Phillips, 1992; Brugnone et al., 1994). Carbon disulfide can be metabolized in the liver by the cytochrome P-450 mono-oxygenase system to an unstable oxygen intermediate that either spontaneously generates atomic sulfur, carbonyl sulfide, and carbon dioxide or hydrolyses to form atomic sulfur and mono-thiocarbonate, yielding carbonyl sulfide and carbon dioxide in breath and inorganic sulfates and organosulfur compounds in urine. In studies of mammalian cells exposed to carbon disulfide in the presence of metabolic activation, there were small and/or equivocal increases in chromatid gaps in human lymphocytes, in unscheduled DNA synthesis in diploid WI-38 cells derived from human embryonic lung tissue, and in sister chromatid exchanges in human lymphocytes. www.inchem.org /documents/cicads/cicads/cicad46.htm   (16671 words)

ATSDR - MMG: Carbon Disulfide Most industrially-used carbon disulfide liquid is yellowish in color and has an unpleasant foul-smelling odor, characteristic of hydrogen sulfide (a contaminant of technical grade carbon disulfide). Mechanisms of toxicity have not been clearly elucidated for carbon disulfide, but are thought to be the result of the formation of carbon disulfide metabolites such as dithiocarbamates and/or derivatives. Inhaled carbon disulfide is readily absorbed and is a respiratory tract irritant. www.atsdr.cdc.gov /MHMI/mmg82.html   (4437 words)

Carbon Disulfide Effects on Animals: Carbon disulfide exposure by inhalation causes significant toxicity to the brain, spleen, liver, and testes, and irritation of the intestinal tract in experimental animals [ACGIH The oral LD(50) in rats is 3,188 mg/kg, and the 2-hour LC(50) in rats is 25 gm/m(3) [NIOSH 1991]. Before a worker is placed in a job with a potential for exposure to carbon disulfide, a licensed health care professional should evaluate and document the worker's baseline health status with thorough medical, environmental, and occupational histories, a physical examination, and physiologic and laboratory tests appropriate for the anticipated occupational risks. Determination of a worker's exposure to airborne carbon disulfide is madeusing a charcoal tube (100/50 mg sections, 20/40 mesh). www.osha.gov /SLTC/healthguidelines/carbondisulfide/recognition.html   (4041 words)

Disulfide Bonds   (Site not responding. Last check: 2007-10-10) Disulfide bonds are formed by the oxidation of thiol (-SH) groups in cysteine residues: Disulfide bonds occur intramolecularly (i.e within a single polypeptide chain) and intermolecularly (i.e. Intramolecular disulfide bonds stabilize the tertiary structures of proteins while thoise that occur intermolecularly are involved in stabilizing quartenary structure. webhost.bridgew.edu /fgorga/proteins/disulfide.htm   (103 words)

Proteins - Tertiary Structure   (Site not responding. Last check: 2007-10-10) Disulfide bonds are formed in an oxidizing environment between cysteine residues in different parts of a protein chain: The looped-out sections of chain contain the antigenic regions; amino acid mutations in these regions alter the antigenic character of the molecule, resulting in the recurring influenza epidemics with which we all are familiar. A reducing environment, of course, cleaves the disulfide bonds and destroys the native conformation. chemistry.umeche.maine.edu /CHY431/Proteins11.html   (428 words)

Formation of Disulfide Bridges by a Single-chain Fv Antibody in the Reducing Ectopic Environment of the Plant Cytosol ... Formation of Disulfide Bridges by a Single-chain Fv Antibody in the Reducing Ectopic Environment of the Plant Cytosol -- Schouten et al. Disulfide bridge formation in the reducing environment of the cytosol is considered a rare event and is mostly linked to inactivation The capability of a scFv antibody to form disulfide bridges in the cytosol is remarkable. www.jbc.org /cgi/content/full/277/22/19339   (4898 words)

215. Carbon disulfide (WHO Pesticide Residues Series 1) Residual carbon disulfide was recovered by an acid distillation procedure and determined colorimetrically. In pilot plant tests the residue of carbon disulfide found in uncleaned wheat treated at the usual commercial dose was about 1 ppm and in the milled products this was reduced to around 0.5 ppm. Canada Carbon disulfide is included in a group of agricultural chemicals which when used according to recommendations for post-harvest application to stored food products, disappear during the subsequent processing of the food or do not have harmful or poisonous residues so that when the food reaches the consumer, no hazard is considered to remain. www.inchem.org /documents/jmpr/jmpmono/v071pr11.htm   (1327 words)

Genomic evidence that the intracellular proteins of archaeal microbes contain disulfide bonds -- Mallick et al. 99 ... Its three disulfide bonds led to the initial suggestion that some hyperthermophilic archaea might be rich in intracellular protein disulfide bonds. The total disulfide abundance for a genome is estimated statistically by comparison with results on sets of control proteins as described in Materials and Methods. of the archaea, because the disulfide abundances of the crenarchaeota www.pnas.org /cgi/content/full/99/15/9679   (3546 words)

EPA - Air Toxics Website - Carbon Disulfide Releases of carbon disulfide from industrial processes are almost exclusively to the air; individuals in proximity to these sites may be exposed. Pharmacokinetic studies indicate that carbon disulfide and its metabolites cross the placenta and localize in the target organs of the fetus (brain, blood, liver, and eyes). Pure carbon disulfide occurs as a colorless liquid that is not very soluble in water; impure carbon disulfide is yellowish. www.epa.gov /ttnatw01/hlthef/carbondi.html   (1449 words)

EPA - Air Toxics Website - Carbon Disulfide Carbon disulfide is used predominantly in the manufacture of rayon, cellophane, and carbon tetrachloride. Concentrations of carbon disulfide in urban/suburban areas were measured at about 65 parts per trillion (ppt) and in rural areas at about 41 ppt. Tests involving acute exposure of rats, mice, and rabbits have shown carbon disulfide to have low acute toxicity from inhalation and moderate acute toxicity by ingestion. www.epa.gov /ttn/atw/hlthef/carbondi.html   (1449 words)

Disulfide By Design Software - A. Dombkowski, Ph.D. Disulfide by Design is an application for the rational design of disulfide bonds in proteins. For a given protein structural model, all residue pairs are rapidly assessed for proximity and geometry consistent with disulfide formation – assuming the residues were mutated to cysteines. Engineered disulfides have proven useful for increasing the stability of proteins and to assist the investigation of protein dynamics and interactions. www.ehscenter.org /dbd   (286 words)

An in vivo pathway for disulfide bond isomerization in Escherichia coli -- Rietsch et al. 93 (23): 13048 -- ... An in vivo pathway for disulfide bond isomerization in Escherichia coli -- Rietsch et al. An in vivo pathway for disulfide bond isomerization in Escherichia coli Mouse urokinase has 12 disulfide bonds, 6 of which are in the serine protease domain. www.pnas.org /cgi/content/full/93/23/13048   (4986 words)

Vicinal disulfide turns -- Carugo et al. 16 (9): 637 -- Protein Engineering Design and Selection   (Site not responding. Last check: 2007-10-10) The disulfide bond formed between the side chains of adjacent In Figure 1 the structure of the vicinal disulfides is compared A few disulfide bonds are indicated with dashed lines. peds.oxfordjournals.org /cgi/content/full/16/9/637   (950 words)

Prolyl Hydroxylase, Protein Disulfide Isomerase and Other Proteins   (Site not responding. Last check: 2007-10-10) This timely resource analyzes the function of specific enzymes in the complex processes of protein conformation, assembly, and stability - comprehensively addressing the folding of proteins to natural states as well as cotranslational and postranslational modifications that effect function. Disulfide Isomerase Gene Family with Thiol Oxidoreductase Activity Subject to Neuroendocrine Regulation. Protein Disulfide Isomerase and the Complications of Protein Folding. www.vonl.com /chips/prolyl.htm   (305 words)

CARBON DISULFIDE Atherosclerotic changes, as indicated by clinical, electrocardiographic, oscillometric, and optic fundi examination and by estimation of cholesterolemia, triglyceridemia, were found in 30.4% of the subjects and arterial hypertension in 23.2%; 14.5% of the workers showed both conditions. Increased urinary and fecal excretion of zinc by the exposed rabbits and a gradual decrease in the mean concentration of zinc in the blood serum /was noted/ during the study. The half-life for hydrolysis at pH 9 extrapolated from measurements at higher pH is 1.1 yr (1). www.frankmckinnon.com /carbon_disulfide.htm   (13997 words)

difurfuryl disulfide   (Site not responding. Last check: 2007-10-10) With over half centurys efforts, CIYUN has built a reputation for dependability and resourcefulness by supplying high quality specialist ingredients to clients in the fields of Flavor, Essence, Organic Fine Chemicals, Agrochemicals and Pharmaceuticals. Since it''s founding in 1922, Tokyo Kasei Kogyo (TKK) has grown to be a leading, international manufacturer and distributor of over 17,000 fine specialty organic chemicals, many of which are rare or very hard to find. We sell natural and pure molecules which are the basis of flavouring substances (delivered with a naturality certificate).We sell also essential oils, concretes, absolutes, resinoïds and oleoresins. www.chemindustry.net /chemnames/D/difurfuryl_disulfide.html   (222 words)

Carbon Disulfide Monitoring Kits   (Site not responding. Last check: 2007-10-10) EMT's Carbon Disulfide Monitoring Kits are designed to provide you with the ability to check exposure levels to Carbon Disulfide. Permissible exposure limit (PEL) for carbon disulfide is Send mail to Webmaster with questions or comments about this web site. www.emt-online.com /ProductPages/KitsCarbonDisulfide.htm   (409 words)

Functional Differences in Yeast Protein Disulfide Isomerases -- Nørgaard et al. 152 (3): 553 -- The Journal of ... Functional Differences in Yeast Protein Disulfide Isomerases -- Nørgaard et al. PDI1 is the essential gene encoding protein disulfide isomerase The Contributions of Protein Disulfide Isomerase and Its Homologues to Oxidative Protein Folding in the Yeast Endoplasmic Reticulum www.jcb.org /cgi/content/abstract/152/3/553   (560 words)

INFORMATION REGARDING CARBON DISULFIDE AND BROMINE   (Site not responding. Last check: 2007-10-10) A 24 year old male, employed in the curing room of an India rubber factory, was exposed to When the quartz lamp was discharged, some vapor of the disulfide which had leaked out, ignited in the radiation flash and exploded. Thirty workers of a viscose rayon industry had a complete eye examination in 1979 including visual acuity, perimetry, color vision testing, fluorescein angiography, ERG and EOG, for possible signs of chronic www.frankmckinnon.com /information_regarding_carbon_dis2.htm   (12651 words)

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