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Protein Science : a Publication of the... Nov 1995The molar absorption coefficient, epsilon, of a protein is usually based on concentrations measured by dry weight, nitrogen, or amino acid analysis. The studies reported...
The molar absorption coefficient, epsilon, of a protein is usually based on concentrations measured by dry weight, nitrogen, or amino acid analysis. The studies reported here suggest that the Edelhoch method is the best method for measuring epsilon for a protein. (This method is described by Gill and von Hippel [1989, Anal Biochem 182:319-326] and is based on data from Edelhoch [1967, Biochemistry 6:1948-1954]). The absorbance of a protein at 280 nm depends on the content of Trp, Tyr, and cystine (disulfide bonds). The average epsilon values for these chromophores in a sample of 18 well-characterized proteins have been estimated, and the epsilon values in water, propanol, 6 M guanidine hydrochloride (GdnHCl), and 8 M urea have been measured. For Trp, the average epsilon values for the proteins are less than the epsilon values measured in any of the solvents. For Tyr, the average epsilon values for the proteins are intermediate between those measured in 6 M GdnHCl and those measured in propanol. Based on a sample of 116 measured epsilon values for 80 proteins, the epsilon at 280 nm of a folded protein in water, epsilon (280), can best be predicted with this equation: epsilon (280) (M-1 cm-1) = (#Trp)(5,500) + (#Tyr)(1,490) + (#cystine)(125) These epsilon (280) values are quite reliable for proteins containing Trp residues, and less reliable for proteins that do not. However, the Edelhoch method is convenient and accurate, and the best approach is to measure rather than predict epsilon.
Topics: 1-Propanol; Chemical Phenomena; Chemistry, Physical; Cystine; Guanidine; Guanidines; Proteins; Solvents; Spectrophotometry, Ultraviolet; Tryptophan; Tyrosine; Urea; Water
PubMed: 8563639
DOI: 10.1002/pro.5560041120 -
Nature Neuroscience Jan 2014Using olfactory molecular specificity, we examined the inheritance of parental traumatic exposure, a phenomenon that has been frequently observed, but not understood. We...
Using olfactory molecular specificity, we examined the inheritance of parental traumatic exposure, a phenomenon that has been frequently observed, but not understood. We subjected F0 mice to odor fear conditioning before conception and found that subsequently conceived F1 and F2 generations had an increased behavioral sensitivity to the F0-conditioned odor, but not to other odors. When an odor (acetophenone) that activates a known odorant receptor (Olfr151) was used to condition F0 mice, the behavioral sensitivity of the F1 and F2 generations to acetophenone was complemented by an enhanced neuroanatomical representation of the Olfr151 pathway. Bisulfite sequencing of sperm DNA from conditioned F0 males and F1 naive offspring revealed CpG hypomethylation in the Olfr151 gene. In addition, in vitro fertilization, F2 inheritance and cross-fostering revealed that these transgenerational effects are inherited via parental gametes. Our findings provide a framework for addressing how environmental information may be inherited transgenerationally at behavioral, neuroanatomical and epigenetic levels.
Topics: 1-Propanol; Acetophenones; Acoustic Stimulation; Analysis of Variance; Animals; Chromatin Immunoprecipitation; Conditioning, Classical; Electroshock; Epigenomics; Fear; Female; Glycine; Male; Mice; Mice, Transgenic; Odorants; Olfactory Pathways; Paternal Exposure; Pregnancy; Receptors, Odorant; Reflex, Startle; Sensory Receptor Cells; Smell; Spermatozoa; beta-Galactosidase
PubMed: 24292232
DOI: 10.1038/nn.3594 -
Canadian Journal of Dental Hygiene :... Oct 2022This narrative review aims to compile and analyse infection prevention and control (IPAC) practices followed by dental clinics during 3 coronavirus outbreaks: SARS... (Review)
Review
OBJECTIVE
This narrative review aims to compile and analyse infection prevention and control (IPAC) practices followed by dental clinics during 3 coronavirus outbreaks: SARS (2002-2004), MERS (2012-2014), and COVID-19 (2019-); and to draw parallels from them for future epidemics.
METHODS
Data were collected from 3 databases: Google Scholar, PubMed, and Embase using search terms "SARS," "MERS," "COVID-19," "infection control," "disinfection," and "sterilization".
RESULTS
Careful examination of 108 peer-reviewed articles on the 3 outbreaks revealed the following commonalities in the IPAC practices of dental clinics: use of sodium hypochlorite (surface disinfectant), ethanol and 1-propanol (hand hygiene), povidone-iodine (oral rinse), high-volume evacuation (HVE), rubber dam isolation, anti-retraction handpieces, and fogging.
DISCUSSION & CONCLUSION
Ethanol, 1-propanol, sodium hypochlorite, povidone-iodine, photocatalysis, and fogging have been shown to be effective against various coronaviruses. However, more studies are required to validate the effectiveness of anti-retraction handpieces, rubber dam isolation, HVE, and cold atmospheric plasma specifically in infection control of the current coronavirus strain, SARS-CoV-2.
Topics: Humans; COVID-19; Povidone-Iodine; 1-Propanol; Sodium Hypochlorite; SARS-CoV-2; Disease Outbreaks; Dental Care; Disinfection
PubMed: 36451994
DOI: No ID Found -
Antimicrobial Resistance and Infection... Nov 2022Reports are available on cross-resistance between antibiotics and biocides. We evaluated the effect of povidone-iodine (PVP-I) and propanol-based mecetronium ethyl...
BACKGROUND
Reports are available on cross-resistance between antibiotics and biocides. We evaluated the effect of povidone-iodine (PVP-I) and propanol-based mecetronium ethyl sulphate (PBM) on resistance development, antibiotics cross-resistance, and virulence in Staphylococcus aureus.
METHODS
The minimum inhibitory concentration (MIC) of PVP-I and PBM were determined against S. aureus ATCC 25923 using the agar-dilution method. Staphylococcus aureus ATCC 25923 was subjected to subinhibitory concentrations of the tested biocides in ten consecutive passages followed by five passages in a biocide-free medium; MIC was determined after each passage and after the fifth passage in the biocide-free medium. The developed resistant mutant was tested for cross-resistance to different antibiotics using Kirby-Bauer disk diffusion method. Antibiotic susceptibility profiles as well as biocides' MIC were determined for 97 clinical S. aureus isolates. Isolates were categorized into susceptible and resistant to the tested biocides based on MIC distribution pattern. The virulence of the biocide-resistant mutant and the effect of subinhibitory concentrations of biocides on virulence (biofilm formation, hemolysin activity, and expression of virulence-related genes) were tested.
RESULTS
PVP-I and PBM MIC were 5000 μg/mL and 664 μg/mL. No resistance developed to PVP-I but a 128-fold increase in PBM MIC was recorded, by repeated exposure. The developed PBM-resistant mutant acquired resistance to penicillin, cefoxitin, and ciprofloxacin. No clinical isolates were PVP-I-resistant while 48.5% were PBM-resistant. PBM-resistant isolates were more significantly detected among multidrug-resistant isolates. PVP-I subinhibitory concentrations (¼ and ½ of MIC) completely inhibited biofilm formation and significantly reduced hemolysin activity (7% and 0.28%, respectively). However, subinhibitory concentrations of PBM caused moderate reduction in biofilm activity and non-significant reduction in hemolysin activity. The ½ MIC of PVP-I significantly reduced the expression of hla, ebps, eno, fib, icaA, and icaD genes. The virulence of the biocide-resistant mutant was similar to that of parent strain.
CONCLUSION
PVP-I is a highly recommended antiseptic for use in healthcare settings to control the evolution of high-risk clones. Exposure to PVP-I causes no resistance-development risk in S. aureus, with virulence inhibition by subinhibitory concentrations. Also, special protocols need to be followed during PBM use in hospitals to avoid the selection of resistant strains.
Topics: Humans; Staphylococcus aureus; Povidone-Iodine; Anti-Bacterial Agents; Virulence; 1-Propanol; Hemolysin Proteins; Drug Resistance, Bacterial; Staphylococcal Infections; Disinfectants
PubMed: 36369050
DOI: 10.1186/s13756-022-01178-9 -
Contact Dermatitis Jan 2021The use of alcoholic-based hand rubs (ABHRs) is an important tool for hand hygiene, especially in times of the COVID-19 pandemic. Possible irritant effects of ABHR may...
BACKGROUND
The use of alcoholic-based hand rubs (ABHRs) is an important tool for hand hygiene, especially in times of the COVID-19 pandemic. Possible irritant effects of ABHR may prevent their use by persons at risk of infection.
METHODS
This systematic review is based on a PubMed search of articles published between January 2000 and September 2019 in English and German, and a manual search, related to the irritation potential of alcohol-based disinfectants restricted to n-propanol (1-propanol) and its structural isomer isopropanol (isopropyl alcohol, 2-propanol).
RESULTS
The majority of the included studies show a low irritation potential of n-propanol alone. However, recent studies provide evidence for significant barrier damage effects of repeated exposure to 60% n-propanol in healthy, as well as atopic skin in vivo. The synergistic response of combined irritants, (ie, a combination of n-propanol or isopropanol with detergents such as sodium lauryl sulfate) is greater, compared with a quantitatively identical application of the same irritant alone.
CONCLUSION
While recent studies indicate a higher risk of skin irritation for n-propanol and isopropanol than reported in the past, this risk still seems to be lower than that for frequent handwashing with detergents, as recommended by some to prevent COVID-19 infections.
Topics: 1-Propanol; 2-Propanol; Anti-Infective Agents, Local; COVID-19; Dermatitis, Irritant; Hand Disinfection; Humans
PubMed: 33063847
DOI: 10.1111/cod.13722 -
IARC Monographs on the Evaluation of... 2000
Review
Topics: Animals; Carcinogenicity Tests; Carcinogens; Cricetinae; Disease Models, Animal; Environmental Exposure; Epoxy Compounds; Female; Humans; Male; Maximum Allowable Concentration; Mice; Neoplasms, Experimental; Propanols; Rats
PubMed: 11100412
DOI: No ID Found -
Molecules (Basel, Switzerland) Jan 2022The forensic toxicologist is challenged to provide scientific evidence to distinguish the source of ethanol (antemortem ingestion or microbial production) determined in... (Review)
Review
The forensic toxicologist is challenged to provide scientific evidence to distinguish the source of ethanol (antemortem ingestion or microbial production) determined in the postmortem blood and to properly interpret the relevant blood alcohol concentration (BAC) results, in regard to ethanol levels at death and subsequent behavioral impairment of the person at the time of death. Higher alcohols (1-propanol, 1-butanol, isobutanol, 2-methyl-1-butanol (isoamyl-alcohol), and 3-methyl-2-butanol (amyl-alcohol)) are among the volatile compounds that are often detected in postmortem specimens and have been correlated with putrefaction and microbial activity. This brief review investigates the role of the higher alcohols as biomarkers of postmortem, microbial ethanol production, notably, regarding the modeling of postmortem ethanol production. Main conclusions of this contribution are, firstly, that the higher alcohols are qualitative and quantitative indicators of microbial ethanol production, and, secondly that the respective models of microbial ethanol production are tools offering additional data to interpret properly the origin of the ethanol concentrations measured in postmortem cases. More studies are needed to clarify current uncertainties about the origin of higher alcohols in postmortem specimens.
Topics: Alcohols; Autopsy; Blood Alcohol Content; Butanols; Ethanol; Forensic Toxicology; Humans; Pentanols; Postmortem Changes; Propanols
PubMed: 35163964
DOI: 10.3390/molecules27030700 -
Food and Chemical Toxicology : An... Jan 20193-NOP (3-nitroxy-propanol) is a new development compound which reduces methane emission from ruminating animals. For registration purposes with emphasis on EU and North...
3-NOP (3-nitroxy-propanol) is a new development compound which reduces methane emission from ruminating animals. For registration purposes with emphasis on EU and North America data requirements, mutagenic and genotoxic potential was assessed following OECD protocols and respective guidance documents. 3-NOP mutagenicity and genotoxicity testing raised no flags with regard to these endpoints. In silico assessment of 3-NOP and its major plasma metabolite NOPA (3-nitroxy-propionic acid) were predicted negative with regard to the bacterial reverse mutation (Ames) test. Ames test, mouse lymphoma assay, in vitro micronucleus test, and the oral in vivo micronucleus test using rat bone marrow were all negative. Exposure of the rat bone marrow was verified by the presence of 3-NOP and its metabolites NOPA and HPA (3-hydroxy-propionic acid) a naturally occurring substance in mammals) in plasma following oral dosing. It is therefore concluded that 3-NOP and its metabolites pose no mutagenic and genotoxic potential.
Topics: 1-Propanol; Animals; Bacteria; Cell Line; DNA Damage; Mice; Micronucleus Tests; Mutagenicity Tests; Mutagens
PubMed: 30408540
DOI: 10.1016/j.fct.2018.11.010 -
Environmental Health Perspectives Dec 1977Haloorganic biocides are widely employed as soil fumigants to combat the destructive action of plant parasitic nematodes and fungi. These substances are dehalogenated by...
Haloorganic biocides are widely employed as soil fumigants to combat the destructive action of plant parasitic nematodes and fungi. These substances are dehalogenated by soil organisms, principally species of Pseudomonas and Flavobacteria, to nontoxic metabolities. The paths of metabolism of a vareity of simply alkyl halides are described with emphasis upon the biodehalogenation step.
Topics: 1-Propanol; Allyl Compounds; Animals; Biotransformation; Butanes; Ethylene Dibromide; Hemeproteins; Hydrocarbons, Chlorinated; Hydrocarbons, Halogenated; Hydrolysis; Nematoda; Oxidation-Reduction; Propane; Propanols; Pseudomonas; Soil Microbiology
PubMed: 348458
DOI: 10.1289/ehp.7721279 -
Report on Carcinogens : Carcinogen... 2011
Topics: Animals; Carcinogens; Humans; Neoplasms; Propanols
PubMed: 21850143
DOI: No ID Found