scholarly journals Effect of Synthetic Detergents on the Swelling and the ATPase of Mitochondria Isolated from Rat Liver

1958 ◽  
Vol 4 (1) ◽  
pp. 73-82 ◽  
Author(s):  
Robert F. Witter ◽  
William Mink
Keyword(s):  
The Other ◽  
Side Chain ◽  
Isolated Mitochondria ◽  
Mitochondrial Structure ◽  
Ionic Detergents ◽  
Cationic Detergents ◽  
Beckman Spectrophotometer ◽  
Dilute Suspensions ◽  
Anionic Detergents ◽  
Protein Moiety

A study was made of the effects of various types of detergents on the swelling of isolated mitochondria and on mitochondrial ATPases which are activated by Mg or DNP respectively. The rate of swelling was measured in the Beckman spectrophotometer by following the decrease in turbidity of dilute suspensions of these organelles. It was found that non-ionic detergents containing a nonyl phenoxy side chain or anionic detergents caused swelling of the mitochondria and activation of Mg-ATPase. On the other hand, cationic detergents promoted the clumping of mitochondria and did not activate Mg-ATPase. DNP-ATPase was inhibited by all of the detergents tested. It would appear from these observations that the inhibition of DNP-ATPase is not related to a gross change in the morphology of the organelles; in contrast, the activation of Mg-ATPase definitely is correlated with swelling of the isolated mitochondria. These data also suggest that the ionic detergents combine with charged sites on the protein moiety of the lipoprotein in the mitochondrial surface, whereas the non-ionic detergents form inclusion compounds with the lipide moiety, thereby altering the mitochondrial structure and permeability.

On haemolysis by anionic detergents

1957 ◽  
Vol 146 (923) ◽  
pp. 225-241 ◽  
Keyword(s):  
Cell Wall ◽  
Blood Cells ◽  
The Other ◽  
Slow Process ◽  
Ionic Detergents ◽  
Human Red Blood Cells ◽  
Lipoprotein Complex ◽  
Rapid Destruction ◽  
Anionic Detergents ◽  
Kinetics Of

The kinetics of haemolysis of human red blood cells by synthetic anionic detergents has been studied. It is shown that these detergents can destroy red cells by two mechanisms, which normally operate simultaneously, one leading to a rapid destruction of the cells whilst the other is a slow process. The rapid process involves the action of the detergent on free phospholipid in the cell wall. This component is easily removed from the cell membrane, and cells thus treated will not undergo rapid haemolysis. The slow process is identical with that by which most haemolytic agents (saponins, non-ionic detergents and butanol) act, and if it alone can operate yields percentage haemolysistime curves which are sigmoid in shape. This process takes place in several stages and seems to involve the slow breakdown of a lipoprotein complex on the cell surface. If phospholipid is removed from the cell wall, it is slowly replaced from phospholipid bound as lipoprotein or possibly by synthesis from metabolites in the membrane. The equilibria which maintain the structure of the cell wall are discussed.

Comparison of the Potency of 8-L-Arginine, 8-D-Arginine and 8-D-Homoarginine Vasopressin Analogs with Substituted Phenylalanine in Position 2

1994 ◽  
Vol 59 (6) ◽  
pp. 1439-1450 ◽  
Author(s):  
Miroslava Žertová ◽  
Jiřina Slaninová ◽  
Zdenko Procházka
Keyword(s):  
Amino Acid ◽  
Solid Phase Synthesis ◽  
Solid Phase ◽  
Basic Amino Acid ◽  
The Other ◽  
Side Chain ◽  
Inhibitory Potency ◽  
Phase Synthesis ◽  
Other Hand ◽  
Order Of Magnitude

An analysis of the uterotonic potencies of all analogs having substituted L- or D-tyrosine or -phenylalanine in position 2 and L-arginine, D-arginine or D-homoarginine in position 8 was made. The series of analogs already published was completed by the solid phase synthesis of ten new analogs having L- or D-Phe, L- or D-Phe(2-Et), L- or D-Phe(2,4,6-triMe) or D-Tyr(Me) in position 2 and either L- or D-arginine in position 8. All newly synthesized analogs were found to be uterotonic inhibitors. Deamination increases both the agonistic and antagonistic potency. In the case of phenylalanine analogs the change of configuration from L to D in position 2 enhances the uterotonic inhibition for more than 1 order of magnitude. The L to D change in position 8 enhances the inhibitory potency negligibly. Prolongation of the side chain of the D-basic amino acid in position 8 seems to decrease slightly the inhibitory potency if there is L-substituted amino acid in position 2. On the other hand there is a tendency to the increase of the inhibitory potency if there is D-substituted amino acid in position 2.

Solubilization and immunoprecipitation of 125I-labelled antigens from Plasmodium knowlesi schizont-infected erythrocytes using non-ionic, anionic and zwitterionic detergents

Parasitology ◽  
1984 ◽  
Vol 88 (1) ◽  
pp. 27-36 ◽  
Author(s):  
R. J. Howard ◽  
J. W. Barnwell
Keyword(s):  
Sodium Dodecyl Sulphate ◽  
Gel Electrophoresis ◽  
Plasmodium Knowlesi ◽  
Polyacrylamide Gel Electrophoresis ◽  
Protein A ◽  
Sodium Dodecyl ◽  
Ionic Detergents ◽  
Class A ◽  
Anionic Detergents ◽  
Triton X

SUMMARYPlasmodium knowlesi malaria-infected erythrocytes were radio-iodinated and several non-ionic, anionic and zwitterionic detergents were compared in their capacity to extract the labelled membrane proteins. The use of these detergents for antigen identification was tested by immunoprecipitation, after addition of Triton X-100 to some detergent extracts, using hyperimmune monkey antiserum and protein A-Sepharose. 125I-labelled antigens were specifically immunoprecipitated with all detergents tested, including the anionic detergents sodium dodecyl sulphate (SDS), deoxycholate and cholate; the zwitterions Zwittergent-312 and -314, CHAPS and Empigen BB, as well as several non-ionic detergents. The SDS-polyacrylamide gel electrophoresis patterns of 125I-labelled antigens varied after extraction with different detergents, there being no consistent pattern for detergents of a particular class. A total of 14 125I-labelled antigens were identified, 11 of them using Triton X-100. Some minor antigens identified with Triton X-100 were immunoprecipitated in greater amount after extraction in other detergents. Most importantly, two antigens Mr 200000 and 180000 were detected only after extraction with deoxycholate or SDS.

Structural Studies on N-(2,4,6-Trimethylphenyl)-methyl/ chloro-acetamides, 2,4,6-(CH3)3C6H2NH-CO-CH3–yXy (X = CH3 or Cl and y = 0, 1, 2)

2006 ◽  
Vol 61 (10-11) ◽  
pp. 588-594 ◽  
Author(s):  
Basavalinganadoddy Thimme Gowda ◽  
Jozef Kožíšek ◽  
Hartmut Fuess
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Structural Data ◽  
The Other ◽  
Side Chain ◽  
Structural Studies ◽  
Asymmetric Unit ◽  
Lattice Constants ◽  
Peptide Linkage ◽  
The Mean

TMPAThe effect of substitutions in the ring and in the side chain on the crystal structure of N- (2,4,6-trimethylphenyl)-methyl/chloro-acetamides of the configuration 2,4,6-(CH3)3C6H2NH-COCH3− yXy (X = CH3 or Cl and y = 0,1, 2) has been studied by determining the crystal structures of N-(2,4,6-trimethylphenyl)-acetamide, 2,4,6-(CH3)3C6H2NH-CO-CH3 (); N-(2,4,6- trimethylphenyl)-2-methylacetamide, 2,4,6-(CH3)3C6H2NH-CO-CH2-CH3 (TMPMA); N-(2,4,6- trimethylphenyl)-2,2-dimethylacetamide, 2,4,6-(CH3)3C6H2NH-CO-CH(CH3)2 (TMPDMA) and N-(2,4,6-trimethylphenyl)-2,2-dichloroacetamide, 2,4,6-(CH3)3C6H2NH-CO-CHCl2 (TMPDCA). The crystallographic system, space group, formula units and lattice constants in Å are: TMPA: monoclinic, Pn, Z = 2, a = 8.142(3), b = 8.469(3), c = 8.223(3), β = 113.61(2)◦; TMPMA: monoclinic, P21/n, Z = 8, a = 9.103(1), b = 15.812(2), c = 16.4787(19), α = 89.974(10)◦, β = 96.951(10)◦, γ =89.967(10)◦; TMPDMA: monoclinic, P21/c, Z = 4, a =4.757(1), b= 24.644(4), c =10.785(2), β = 99.647(17)◦; TMPDCA: triclinic, P¯1, Z = 2, a = 4.652(1), b = 11.006(1), c = 12.369(1), α = 82.521(7)◦, β = 83.09(1)◦, γ = 79.84(1)◦. The results are analyzed along with the structural data of N-phenylacetamide, C6H5NH-CO-CH3; N-(2,4,6-trimethylphenyl)-2-chloroacetamide, 2,4,6-(CH3)3C6H2NH-CO-CH2Cl; N-(2,4,6-trichlorophenyl)-acetamide, 2,4,6-Cl3C6H2NH-COCH3; N-(2,4,6-trichlorophenyl)-2-chloroacetamide, 2,4,6-Cl3C6H2NH-CO-CH2Cl; N-(2,4,6-trichlorophenyl)- 2,2-dichloroacetamide, 2,4,6-Cl3C6H2NH-CO-CHCl2 and N-(2,4,6-trichlorophenyl)- 2,2,2-trichloroacetamide, 2,4,6-Cl3C6H2NH-CO-CCl3. TMPA, TMPMA and TMPDCA have one molecule each in their asymmetric units, while TMPDMA has two molecules in its asymmetric unit. Changes in the mean ring distances are smaller on substitution as the effect has to be transmitted through the peptide linkage. The comparison of the other bond parameters reveal that there are significant changes in them on substitution.

Are mesoionic compounds aromatic?

1998 ◽  
Vol 76 (6) ◽  
pp. 869-872 ◽  
Author(s):  
Alfredo Mayall Simas ◽  
Joseph Miller ◽  
Petrônio Filgueiras de Athayade Filho
Keyword(s):  
Experimental Evidence ◽  
Key Words ◽  
Dipole Moments ◽  
The Other ◽  
Side Chain ◽  
Theoretical Studies ◽  
X Ray Diffraction ◽  
Ring Plane ◽  
X Ray ◽  
Single Bonds

We have evaluated the experimental evidence relevant to the structure and character of mesoionic compounds, accumulated for more than 100 years and including X-ray diffraction studies. We have also evaluated relevant theoretical studies. All these, including our own extensive work, lead us to conclude that mesoionic compounds are not aromatic. According to our recent definition “mesoionic compounds are planar five-membered heterocyclic betaines with at least one side chain whose α-atom is also in the ring plane and with dipole moments of the order of 5 D. Electrons are delocalized over two regions separated by what are essentially single bonds. One region, which includes the a-atom of the side chain is associated with the HOMO and negative π-charge whereas the other is associated with the LUMO and positive π-charge.” Key words: mesoionic compounds, betaines, aromaticity.

scholarly journals Effects of mrpigG on Development and Secondary Metabolism of Monascus ruber M7

2020 ◽  
Vol 6 (3) ◽  
pp. 156
Author(s):  
Li Li ◽  
Fusheng Chen
Keyword(s):  
Biosynthetic Pathway ◽  
Gene Deletion ◽  
The Other ◽  
Side Chain ◽  
Asian Countries ◽  
Monascus Ruber ◽  
Monascus Pigments ◽  
The World ◽  
Carbon Side Chain ◽  
Yellow Pigments

Monascus pigments (MPs) have been used as food colorants for several centuries in Asian countries and are now used throughout the world via Asian catering. The MP biosynthetic pathway has been well-illustrated, but the functions of a few genes, including mrpigG, in the MP gene cluster are still unclear. In the current study, in order to investigate the function of mrpigG in M. ruber M7, gene deletion (ΔmrpigG), complementation (ΔmrpigG::mrpigG) and overexpression (M7::PtrpC-mrpigG) mutants were successfully obtained. The morphologies and biomasses, as well as the MP and citrinin production, of these mutants were analyzed. The results revealed that the disruption, complementation and overexpression of mrpigG showed no apparent defects in morphology, biomass or citrinin production (except MP production) in ΔmrpigG compared with M. ruber M7. Although the MP profiles of ΔmrpigG and M. ruber M7 were almost the same—with both having four yellow pigments, two orange pigments (OPs) and two red pigments (RPs)—their yields were decreased in ΔmrpigG to a certain extent. Particularly, the content of rubropunctatin (an OP) and its derivative rubropunctamine (an RP) in ΔmrpigG, both of which have a five-carbon side chain, accounted for 57.7%, and 22.3% of those in M. ruber M7. On the other hand, monascorubrin (an OP) and its derivative monascorubramine (an RP), both of which have a seven-carbon side chain, were increased by 1.15 and 2.55 times, respectively, in ΔmrpigG compared with M. ruber M7. These results suggest that the MrPigG protein may preferentially catalyze the biosynthesis of MPs with a five-carbon side chain.

Effects of non-ionic and anionic detergents on lipid-associated tissue ferritin.

1988 ◽  
Vol 34 (1) ◽  
pp. 152-154
Author(s):  
B E Cham ◽  
P Roeser ◽  
A Nikles
Keyword(s):  
Guinea Pig ◽  
Liver Homogenate ◽  
Diisopropyl Ether ◽  
Detergent Concentration ◽  
Pig Liver ◽  
Ionic Detergents ◽  
Ionic Detergent ◽  
Anionic Detergents ◽  
Triton X ◽  
Guinea Pig Liver

Abstract Lipid-associated ferritin from homogenates of guinea pig liver is released from its conjugate(s) by incubation with the non-ionic detergents Triton X-100 and Nonidet P-40 but not by incubation with the anionic detergent deoxycholate. The amount of lipid-associated ferritin released from its conjugate(s) depends on the concentration of the non-ionic detergents. At a final non-ionic detergent concentration of about 20 g/L, all lipid-associated ferritin is released from its conjugate(s) in a liver homogenate. The amount released is identical with the amount of the lipid-associated ferritin obtained by extraction of the same liver homogenate with a mixture of butanol and diisopropyl ether.

EFFECTS OF SOLVENTS AND SURFACE-ACTIVE AGENTS ON PLASTID PHOSPHATIDASE C ACTIVITY

1957 ◽  
Vol 35 (1) ◽  
pp. 127-142 ◽  
Author(s):  
Morris Kates
Keyword(s):  
Ethyl Ether ◽  
Butyl Acetate ◽  
Cyclic Ethers ◽  
Surface Active Agents ◽  
Cationic Detergents ◽  
Propyl Ketone ◽  
Surface Active ◽  
Anionic Detergents ◽  
High Concentrations ◽  
Aliphatic Ethers

Large stimulations of plastid phosphatidase C activity were produced by (i) linear aliphatic ethers, ketones, and esters; (ii) mixtures of methanol with ethyl ether, petroleum ether, or benzene; and (iii) anionic detergents. Cyclic ethers, ketones, or esters and also alcohols, aldehydes, halogenated compounds, or hydrocarbons produced relatively small stimulations; cationic or non-ionic detergents produced little or no stimulation. The stimulations produced by linear aliphatic ethers, ketones, or esters varied greatly with the chain length of the hydrocarbon groups attached to the oxygen functional group: in each respective class, the most effective solvents were ethyl ether, n-propyl ketone, methyl pentyl ketone, ethyl butyrate, and butyl acetate. The most probable mechanism for explaining the stimulation effect is concluded to be one which involves adsorption of the stimulating solvents at the surfaces of the lecithin and plastid particles in a manner which makes these surfaces lipophilic and thus mutually attracting.In general water-insoluble solvents (ethers, ketones, esters, hydrocarbons) produced relatively little inactivation of enzymatic activity, while water-miscible solvents (alcohols, cyclic ethers, etc.) were strongly inactivating, especially at high concentrations (60–70%). Anionic detergents were not inhibitory in the concentration range in which they were stimulating (< 0.02 M), but were inhibitory at higher concentrations; cationic detergents were strongly inhibitory at all concentrations.It is concluded that extraction of plant phosphatides without concomitant enzymatic degradation should be possible by the use of i-propanol or n-propanol as solvent.

scholarly journals The introduction of the C-22–C-23 ethylenic linkage in ergosterol biosynthesis

1968 ◽  
Vol 106 (3) ◽  
pp. 623-626 ◽  
Author(s):  
M Akhtar ◽  
M. A. Parvez ◽  
P. F. Hunt
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Chemical Synthesis ◽  
Good Yield ◽  
The Other ◽  
Side Chain ◽  
Ergosterol Biosynthesis ◽  
Hydrogen Atoms ◽  
Whole Cells ◽  
C 23 ◽  
Methylene Derivative

Methods for the chemical synthesis of [23−3H2]lanosterol, [23,25−3H3]24-methyldihydrolanosterol and [24,28−3H2]24-methyldihydrolanosterol are described. It is shown that, in the biosynthesis of ergosterol from [26,27−14C2,23−3H2]lanosterol by the whole cells of Saccharomyces cerevisiae, one of the original C-23 hydrogen atoms is lost and the other is retained at C-23 of ergosterol. It is also shown that 24-methyldihydrolanosterol is converted into ergosterol in good yield and without prior conversion into a 24-methylene derivative. On the basis of these results possible pathways for the formation of the ergosterol side chain from a 24-methylene side chain are discussed.

scholarly journals 3-Acetyl-1-(2,6-dichlorophenyl)thiourea

2012 ◽  
Vol 68 (8) ◽  
pp. o2307-o2307
Author(s):  
Sharatha Kumar ◽  
Sabine Foro ◽  
B. Thimme Gowda
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Dihedral Angle ◽  
Title Compound ◽  
The Other ◽  
Side Chain ◽  
Compound C

In the title compound, C9H8Cl2N2OS, the conformation of one of the N—H bonds isantito the C=S group and the other isantito the C=O group. Further, the conformations of the amide C=S and the C=O group areantito each other. The 2,6-dichlorophenyl ring and the 3-acetylthiourea side chain are inclined to one another at a dihedral angle of 83.44 (5)°. An intramolecular N—H...O hydrogen bond occurs. In the crystal, molecules form inversion dimers through pairs of N—H...S hydrogen bonds.

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