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In the present paper we report the results of a study on the base specificity and affinity of eight dyes potentially able to interact with DNA. These compounds include four triphenylmethane dyes used in histochemistry, auramine, "Hoechst 33258" and two acridines substituted with t-butyl groups. They were selected with regard to their inability to intercalate between the base pairs of helical polynucleotides due to -structural limitations. Hydrodynamic studies performed with the DNA complexes of crystal violet and Hoechst 33258 confirmed our assumptions that compounds of this type bind to the outside of DNA. The main results from DNA binding studies indicate that the triphenylmethane dyes except p-fuchsin are bound with high preference to two adjacent A · T pairs while Hoechst 33258 seems to need three A · T pairs as the binding site. Model studies with synthetic polynucleotides revealed that not only a sequence of A · T pairs, but also their structural arrangement in a helix, is crucial for the high affinities observed for most of the ligands when interacting with natural DNA. Methyl green and Hoechst 33258 can be used for increasing the resolution power of cesium chloride density gradients for DNAs with different (A + T) content. [ABSTRACT FROM AUTHOR]

The appearance of intermediates and products in the transformation of 4-androstene-3,17-dione and testosterone to estrone and 17β-estradiol by human placental microsomes was studied. The variables investigated were time, temperature and the concentrations of reduced pyridine nucleotides and of testosterone. The relative amounts of metabolites were markedly influenced by all of the factors studied except temperature, although the reaction velocity at 37 °C was about twice that at 27 °C. Oxidoreduction at C-17 in starting material, intermediates and products was examined using a mixture of [4-14C]testosterone and [7β,17α-²H2]testosterone as substrate. Oxidation and reduction at C-17 was most prominent at the beginning and the end of the reaction sequence. 17α-Hydroxy-5α-androst-1-en-3-one was found to be an inhibitor of the C19 17β-hydroxysteroid dehydrogenase activity of human placental microsomes. [ABSTRACT FROM AUTHOR]

Using young plants of Lycopersicum esculentum Mill., we attempt to define a system for a new evaluation of the physiological role of polyphenols, particularly of their regulating properties on growth and development. Exogenously supplied quinic acid causes an important increase of the phenolic content and a reduced growth of the plants. The decrease in size is proportional to the stimulation of the phenolic pool and is equally obtained using other precursors of aromatic compounds like phenylalanine and cinnamic acid. Non-precursors of polyphenols structurally related to quinic acid are ineffective. It appears from these data that polyphenol levels and growth could be related in tomato plant and that this material would be convenient for studies on interactions between growth and polyphenols. [ABSTRACT FROM AUTHOR]

Bibliographic sources for the complex subject of aroma chemicals are reviewed. The references are not comprehensive but are those which we found to be of value in finding out some of the opportunities for contact with a sensitizing chemical compound, cinnamic aldehyde [ABSTRACT FROM AUTHOR]

Mouse tail scale epidermis was used as a model to evaluate anti-parakeratotic activity of tar oil acids (phenols) boiling between 175 and 400°C. Lower boiling phenols seemed to cause more irritation, whereas high boiling phenols caused granular layer induction in formerly parakeratotic skin. [ABSTRACT FROM AUTHOR]

In a study of ninety-one normal newborn infants it has been shown that, contrary to long-standing belief, it is usual to detect eccrine sweating over the palm towards the end of the first day of life. Sweat testing was performed without any form of stimulation, using a 5% solution of 0-phthaldialdee hyde in xylene. [ABSTRACT FROM AUTHOR]

A benzene-utilizing strain of Moraxella B (genus/Acinetobacter) was isolated from Rhine water. Cell-free extracts of this bacterium, which is highly specific for the oxidation of benzene, require for this process catalytic amounts of NADH. This is regenerated during the course of the reaction by the dehydrogenation of cis-cyclohexadiene-diol to pyrocatechol. The oxygenase system contains nonheme-iron in the form of strongly bound Fe2+. It incorporates two atoms of oxygen simultaneously, as proven by isotope experiments; it is thus a dioxygenase. cis-l,2-Dihydroxy-dihydrobenzene was isolated as the first identifiable stable intermediate. This is further oxidized to pyrocatechol which is then eventually complexly metabolized via the 3-oxoadipic acid pathway. [ABSTRACT FROM AUTHOR]

The magnetic circular dichroism (MCD) induced in the wavelength region of absorption by the aromatic chromophores of a number of proteins has been examined. The major contribution to the MCD is from the tryptophanyl chromophores and to a much lesser extent the tyrosyl chromophores. The magnetically induced CD of tryptophanyl residues is independent of the environment of the residue as indicated by the insensitivity of the MCD to protein denaturation. These characteristics make MCD a valuable analytical tool for the determination of tryptophan in proteins. Determinations of tryptophan content by this method on 9 proteins containing 0—6 tryptophanyl residues per molecule are reported. Certain features of MCD and natural CD are compared with particular attention to azurin and several mammalian carbonic anhydrases which have large natural ellipticity bands associated with the aromatic chromophores. [ABSTRACT FROM AUTHOR]

1. The biosynthesis of alkaloids with 2-phenyl-3-benzazepine skeleton (rhoeadine type) starts from two molecules of tyrosine. Now it was shown, using Papaver bracteatum plants, that [N-14CH3, 8-14C]DL-tetrahydropalmatine methiodide (Ia) is incorporated with high efficiency into alpinigenine (III). Apparently the incorporation of the N-quaternary salt is a specific one. 2. A degradation sequence was applied which allows the selective determination of the radio- activity in the non-aromatic C-atoms as well as the aromatic rings of alpinigenine. 3. The incorporation of a compound with tetrahydroprotoberberine structure is in accordance with current biogenetic views. But involvement of a N-quaternary intermediate seems quite surprising. A novel mechanism of ring rearrangement may operate. Thus, ring splitting as a step for further transformation of tetrahydropalmatine should be initiated by N-methylation followed by hydroxylation on one of the α-C-atoms (C-14 or C-8) and subsequent hydrolysis. 4. The significance of the feeding experiments in respect to biogenesis of benzazepine alkaloids is briefly discussed. [ABSTRACT FROM AUTHOR]

One of the key enzymes in the regulation of aromatic acid biosynthesis, chorismate mutase, has been purified about 3000-fold from cell-free extracts of Euglena gracilis. The enzyme possesses an apparent molecular weight of 160 000. Judged by our criteria Euglena possesses only one species of chorismate mutase. The purified enzyme is sensitive to inhibition by tyrosine and phenylalanine and to activation by tryptophan; the extent of inhibition and activation is strictly pH-dependent. The inhibition by phenylalanine and by tyrosine is partially competitive with chorismate. Substrate saturation data of the effector-free enzyme analyzed by the Hill equation yield values of n of 2.0 at pH 8.4 and of close to 1.0 at pH 7.0, thus indicating strong cooperative interactions under the former and little or no interactions under the latter condition. At pH 7.0 the presence of the inhibitors results in an increase of the value of n suggesting cooperativity under this condition. Little or no cooperative interaction between the inhibitor sites was observed (n' = 1.2). In the presence of tryptophan chorismate mutase exhibits strict Michaelis kinetics (n = 1.0 at pH 7.0 and 8.4). [ABSTRACT FROM AUTHOR]

Changes induced on addition of the cofactor, NAD, to glyceraldehyde-3-phosphate dehydrogenase from yeast have been investigated by hydrodynamic and spectroscopic techniques. As shown by light-scattering and sedimentation and diffusion studies, the tetrameric structure of the holoenzyme persists under all but strong dissociating conditions: there is thus no change in the quaternary structure on binding. On the other hand, landing is accompanied by an increase of some 40/0 in the sedimentation coefficient, which is too large to he explicable in terms of the increase in particle weight by bound ligand. A conformational change is also observed by optical rotatory dispersion and circular dichroism measurements. The magnitude of the Cotton effect associated with the aromatic chromophores of the protein, near 280 nm, increases, whereas the rotation in the neighbourhood of 233 urn undergoes a small diminution as the cofactor is added. it is shown that these changes are conformational in origin, rather than a consequence of WAD attachment per 89. Increasing the temperature in the range 2O-4O° leads to a transition from non-cooperative to cooperative binding of NAD to the apoenzyrne. At 40°, where NAT) binding is weakly sigmoidal, the change in optical rotation is likewise sigmoidal and parallels the increase in the sedimentation coefficient. At 20° both the uptake of WAD and the structural changes arc hyperbolic, in the cooperative situation the data are shown to be consistent with the two-state "concerted" model for ligand-binding and incompatible with a sequential mechanism. [ABSTRACT FROM AUTHOR]

A decrease of the optical rotation in the wavelength region from 200 to 250 mμ is observed when ligands bind to hemoglobin. The change at 233 mμ amounts to about 8% of the total rotation at this wavelength, independently of the nature of the ligand (O2, CO, NO or ethylisocyanide). The effect is interpreted as being caused by a small conformational change, which influences the electronic transitions of a number of peptide bonds or (and) a few aromatic side chains. The change is observed with αβ-dimers, but not with the isolated single chains. The full effect is present however, in chemically modified hemoglobins which no longer show cooperative interactions in the ligand equilibrium curve. It is speculated that the conformational change takes place within the protomers but only when these are joined in αβ-dimers (or tetramers). The chemical modifications might not prevent the initial ligand-induced conformational change, but only abolish the transmission of the conformational change from one subunit to the others. [ABSTRACT FROM AUTHOR]

A new alcohol dehydrogenase preferably acting on aromatic primary alcohols (resp. aldehydes) has been isolated from mycelia of the fungus Neurospora crassa. The enzyme was purified about 450-fold by protamine treatment, ammonium sulphate fractionation, adsorption on calcium phosphate gel, and chromatography on Sephadex G-200 and DEAE-cellulose. Its molecular weight was tentatively estimated to be about 75,000 by use of a calibrated Sephadex G-200 column. The enzyme needs NADPH as cofactor; with NADH, the velocity of the reaction is decreased to less than 1 % of the rate achieved with NADPH. Maximum rates of reaction were observed in the case of aldehyde reduction at pH 6.8; in the reverse reaction, pH 8.8 was optimal. By raising the temperature of the incubation mixture, a linear increase of the reaction velocity up to 55° was noted. The enzyme shows a broad range of substrate specificity towards both aromatic and to a lesser extend aliphatic aldehydes (resp. alcohols). The equilibrium constant K = (aldehyde) (.NADPH) (H+) was determined as about 10-10.(alcohol) (NADP+) Treatment of the enzyme with iodosobenzoate and p-chloromercuribenzoate resulted in an inhibition, while N-ethylmaleimide and iodoacetate had no effect. Substrate specificity studies as well as other properties indicate that this enzyme differs from any known alcohol dehydrogenase. We propose the systematic name aryl alcohol: NADP oxidoreductaze (EC 1.1.1.2). [ABSTRACT FROM AUTHOR]

The inducible enzymes responsible for the dissimilation of aromatic compounds through the β-ketoadipate pathway by Moraxella calcoacetica are subject to a high degree of coordinate control. The five enzymes which catalyze the conversion of protocatechuate to β-ketoadipyl-CoA are coordinately synthesized, the probable inducer being protocatechuate. In the conversion of catechol to β-ketoadipyl-CoA, there are two separate inductive events, though both are mediated by one metabolite-inducer, cis-cis-muconate. One is the induction of catechol oxygenase; the other is the coordinate induction of the four enzymes that catalyze conversion of cic,cis-muconate to β-ketoadipyl-CoA. Although the catechol and protocatechuate branches of the β-ketoadipate pathway converge metabolically with the formation of β-ketoadipate enol-lactone, the two step-reactions required for the conversion of this intermediate to β-ketoadipyl-CoA are mediated by two isofunctional sets of inducible enzymes, one controlled coordinately with enzymes mediating steps specific to the catechol branch, the other coordinately with enzymes mediating steps specific to the protocatechuate branch. The differing control mechanisms which govern synthesis of the enzymes of the β-ketoadipate pathway in Moraxella calcoacetica and in Pseudomonas putida are compared and discussed. [ABSTRACT FROM AUTHOR]

The inhibitory principles of aqueous extracts of aspen leaves, acting upon mycorrhizal fungi of forest trees, were isolated by extraction with ethyl acetate and chromatography on silicic acid. Two inhibitors were identified as benzoic acid and catechol by gas chromatography and mass spectrometry. When added to a synthetic medium, these substances had a strong inhibitory effect on the growth of different Boletus-species and a weaker inhibitory effect on litter-decomposing Marasmius-species. When the fraction of the extract which was not soluble in ethyl acetate was included in the medium the aromatic compounds still inhibited the mycorrhizal fungi while the growth of the litter-decomposers was stimulated. [ABSTRACT FROM AUTHOR]

14C-labelled fluorescein isothiocyanate was synthesized from uniformly labelled [14C]benzene. Radioactive measurements of the amount of 14C-labelled dye in a globulin conjugate gave a ratio of 14.7 μg of dye per mg of globulin. The potential uses of this double tracer are discussed. [ABSTRACT FROM AUTHOR]

Indole, α- and β-naphtol are synergistic with auxins in enhancing root production of cuttings of Phaseolus vulgaris. To find an explanation for this synergism the activity was compared with that of phenolic compounds which are known to be: a. inhibitors of the IAA oxidase system, b. cofactors of the conversion of tryptophane to IAA. Both processes appeared to occur in the bean cuttings (as estimated by root production), but none of the phenols had an activity equally strong as the "synergists". It is suggested that indole as well as α- and β-naphtol act as other injurious substances in "just sublethal" dose (Soekarjo 1966). [ABSTRACT FROM AUTHOR]

The influence of some aromatic compounds, particularly aniline and p-hydroxybenzoic acid, on the growth of Polyporus versicolor and some other hymenomycetes was investigated. Many of these compounds had a growth-promoting effect on P. versicolor. Such an effect was not obtained with p-aminobenzoic acid, tryptophan, or folic acid, indicating that the compounds tested do not function as precursors in the synthesis of these substances. The compounds were active already in small amounts, e.g., aniline at a concentration of 10-5 M. Growth stimulation by aniline and p-hydroxybenzoic acid was observed also with other fungi, but only in laccase-producing species, which seems to imply that the system laccase+phenol (or+amine) plays a special role in the metabolism of these fungi. It is suggested that the system functions as an auxiliary electron transport mechanism, possibly for reoxidation of reduced NAD (DPN). [ABSTRACT FROM AUTHOR]

Dinitrophenol was found to increase the total uptake and active accumulation of calcium by potato slices when supplied at a concentration of 5.9×10-5 moles DNP/liter. Rubidium uptake by potato and both rubidium and calcium uptake by carrot slices were inhibited by this same concentration of DNP. At higher concentrations DNP was found to increase the uptake of calcium into potato slices while reducing the accumulation into the vacuole at the same time. A theory to explain this dual effect was proposed. [ABSTRACT FROM AUTHOR]

The influence of tyrosine and some other substances (amino acids, aromatic compounds) on the growth and laccase production of Polyporus zonatus and P. versicolor has been studied. Several of the compounds tested caused an increased laccase formation, although none was oxidized by the enzyme formed. Strong effects were obtained with tyrosine and p-hydroxybenzoic acid; tryptophan, anthranilic acid, and indole. Phenylalanine had only a very weak action. The findings are discussed in the light of current ideas of enzymatic adaptation. [ABSTRACT FROM AUTHOR]

It is found that technical methoxone prepared from methylphenol contains about 60 per cent 2-methyl,4-chlorophenoxyacetic acid and 40 per cent impurities consisting of different phenols and phenoxyacetic acids. The purpose of this investigation was to show how the effects of pure methoxone were influenced by these impurities and if they affected the specific response of plants. Wheat, peas, mustard, and oil-flax were treated for four hours with methoxone, or an impurity, or both combined. After this they were kept under constant normal conditions and their development was followed. The different sensitivity of plant species is clearly expressed even when the preparation is directly supplied to the roots. The selectivity may be more closely connected with internal conditions of the plants and is not only dependent upon wetting and rate of absorption through the leaves. The impurities modify (he effects of methoxone in three ways, 2-methylphenol, 6-chloro.,2-methylphenol, and 2 methylphenoxyacetic acid work us antagonists and thus decrease the effects of methoxone, 6-chloro,2-methylphenoxyacetic acid gives hormon-like effects and enhances methoxone, 4-chloro,2 methylphenol, 4,6-dichloro,2-melhylphenol and 4,6-dichloro,2-methylphenoxyacetic acid do not alter the methoxone effects but are comparatively toxic to the plants. There is an obvious parallellism between the chemical structure of the compounds and their effects. The varying sensitivity of the different plant species is modified by the impurities. [ABSTRACT FROM AUTHOR]

From heartwood of Western Red Cedar (Thuja plicata D. Don.) Erdtman and collaborators have isolated three isomeric compounds, α-, β-, and γ-thujaplicin, with the empiric formula C10H12O2. These compounds have a strong fungicidal effect upon blueing and decay fungi in malt extract agar. Decay fungi are inhibited in concentrations between 0.001 and 0.002 per cent γ-thujaplicin (10--20 p.p.m.). Phenol, tested in the same way, inhibits the decay fungi in 0.1--0.2 per cent concentrations. Blueing fungi are completely inhibited in a solution of 0.01--0.02 per cent, and considerable inhibition can be observed in a solution of 0.002--0.005 per cent γ-thujaplicin. The growth of the blueing fungi ceased in agar, containing 0.1 per cent phenol. Of the isomeric compounds tested according to the agar diffusion method β-thujaplicin is most toxic, and γ-thujaplicin is some more toxic than α-thujaplicin. Thujaplicin is about as active as sodium pentachlorophenol. [ABSTRACT FROM AUTHOR]

Vehicles influence the penetration of therapeutic agents applied to the skin surface. Physical factors such as temperature and humidity are also of importance. Similarly vehicles and physical factors regulate the retention of material within the stratum corneum to form a reservoir. Penetration of testo-sterone, oestradiol, hydrocortisone, fluocinolone acetonide and griseofulvin, and the influence of of dimethylsulphoxide, dimethylacetamide, dimethylformamide, alcohols and benzene, on percutaneous absorption has been quantitated and related to the influence of these vehicles on the reservoir in separated epidermis with stratum corneum. Similarly, semi-solid vehicles such as ointments have been studied. The experiments indicate that vehicles which enhance penetration also increase the quantity of material retained in the reservoir. [ABSTRACT FROM AUTHOR]

The article presents information on a study regarding immunological investigation of individuals with toluene diisocyanate asthma. Thirteen subjects who experienced only the expected irritant respiratory and ocular effects from occupational exposure to toluene diisocyanate (TDI) were compared with eight workers who appeared clinically to be sensitized to this substance, as manifested by the prompt development of asthmatic symptoms on exposure to minute concentrations of TDI. Since TDI has a marked irritant action on mucous membranes, respiratory symptoms and injury would be expected following inhalation of high concentrations of this substance.

The article states that for many years chemists have had devices for precisely communicating information about individual chemical compounds. The structural formula and the molecular model are two of the more effective devices for precisely and rapidly communicating most of the important structural information about individual chemical compounds. An example of a structural formula is that of the compound 1-iodo-4-nitrobenzene. An example of a molecular model (in two dimensions) is that of methane, CH4.

The clinical patterns of photo-allergic contact dermatitis from several halogenated phenolic compounds which have been recorded in England, United States of America and Australia are described and discussed. Both transient and persistent light reactions have been seen in each country. The variability of clinical presentation resulted from the different ways in which the photo-allergens were applied, either in soaps or in local medicinal preparations such as antiseptic or antifungal creams. Both the reactivity of each photo-allergen and the availability of ultra-violet light to cause it to react are important. The different clinical patterns which should arouse suspicion of photo-allergic contact dermatitis are listed. It is suggested that these variable clinical pictures are essentially the result of the same biochemical mechanism and that photo-allergic dermatitis, whether it occurs at the area of contact or at a distance, is the result of changes at the skin site m conjunction with immunological changes and not as the result of immunological changes akin to autosensitization. [ABSTRACT FROM AUTHOR]

The temperature dependence of the association constant (Ki) of these α-chymotrypsin active centre interaction with some aromatic and aliphatic compounds has been studied (at pH 8.0). The following results are discussed: 1. It was found that log Ki is linearly dependent on 1/T over the 0-30° range. 2. The enthalpy of binding of the benzene derivatives studied was observed to be approximately equal to - 4.5 kcal/mole. 3. The enthalpy increment of the enzyme-inhibitor complex formation for any aliphatic hydrocarbon fragment of inhibitor molecule is near to zero. [ABSTRACT FROM AUTHOR]

Polyureas are shown to be useful finishing agents for wool textiles. They can be applied interfacially to the Wool to yield products with improved ease-of-care properties. The study reports the variations noted in textile properties of treated materials as a function of the structure of the polyurea. Copolyureas from long-chain aliphatic diisocyanates were examined for softening of the stiffer polyureas from aromatic isocyanates. Advantages and disadvantages of polyurea finishes, compared with other polymeric finishes, are pointed out. The Investigation also includes evidence for grafting to the wool substrate. [ABSTRACT FROM AUTHOR]

Because of the allegation that butylated hydroxytoluene produced depigmentation in man, a prospective study was performed. Sixteen adult darkly pigmented males received daily occlusive applications for 60 days. Depigmentation was not observed. [ABSTRACT FROM AUTHOR]

Presents a case of palm and scalp pigmentation in a 37-year-old man after two years of using proprietary hair tonics, containing various phenols and phenolic derivatives. Observation of a light yellow tint in the skin of the center of the palm; Inobservance of any symptoms of dermatitis; Disappearance of the palms and temples pigmentation after two weeks of quitting the hair tonics with phenolic derivatives.