Hypothyroidism in rats does not lower mitochondrial ADP/O and H+/O ratios

We investigated reports that mitochondria isolated from hypothyroid rats have decreased ADP/O and H+/O ratios. We observed no decrease in the H+/O ratio in mitochondria from hypothyroid rats, in the presence of either 2% (w/v) fatty-acid-free bovine serum albumin or 100 nM free Ca2+. The ADP/O ratio in mitochondria isolated from hypothyroid rats in the presence of 2% fatty-acid-free bovine serum albumin was measured. Under normal experimental conditions we found no decrease in the ADP/O ratio, relative to that measured for littermate controls. At the low concentrations of mitochondrial protein used in the previously reported studies, the ADP/O ratio of mitochondria from hypothyroid rats was decreased, whereas that for control rats was only slightly decreased. The difference between the ADP/O ratios measured for mitochondria form hypothyroid rats and from control rats under these conditions was eliminated by inhibition of endogenous adenylate kinase. We suggest that the lowering of the apparent ADP/O ratio in mitochondria from hypothyroid rats at low concentrations of mitochondrial protein is an experimental artefact resulting from the breakdown of ADP to AMP.

Download Full-text

Bovine serum albumin. Study of the fatty acid and steroid binding sites using spin-labeled lipids.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)41627-x ◽

1975 ◽

Vol 250 (7) ◽

pp. 2487-2494

Author(s):

JD Morrisett ◽

HJ Pownall ◽

AM Gotto

Keyword(s):

Fatty Acid ◽

Bovine Serum Albumin ◽

Serum Albumin ◽

Binding Sites ◽

Bovine Serum ◽

Steroid Binding

Download Full-text

Location of long chain fatty acid-binding sites of bovine serum albumin by affinity labeling.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)66760-2 ◽

1986 ◽

Vol 261 (33) ◽

pp. 15619-15624 ◽

Cited By ~ 2

Author(s):

R G Reed

Keyword(s):

Fatty Acid ◽

Bovine Serum Albumin ◽

Serum Albumin ◽

Binding Sites ◽

Bovine Serum ◽

Chain Fatty Acid ◽

Affinity Labeling ◽

Long Chain Fatty Acid ◽

Fatty Acid Binding ◽

Long Chain

Download Full-text

Evaluación del método dilución neutralización aplicado a un desinfectante según la Norma Técnica Colombiana 5473 de 2007

Universitas Scientiarum ◽

10.11144/javeriana.sc17-1.aotd ◽

2012 ◽

Vol 17 (1) ◽

pp. 72

Author(s):

Janeth Arias-Palacios ◽

Libardo Hernandez-Esquivel ◽

Juan Carlos Marín-Díaz ◽

Natalia Navarro-Peña ◽

Natalia Santos-Arévalo

Keyword(s):

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Bovine Serum Albumin ◽

Serum Albumin ◽

Key Words ◽

Bactericidal Activity ◽

Bovine Serum ◽

Enterococcus Hirae ◽

Experimental Conditions ◽

Logarithmic Reduction

Objective. Evaluate the dilution-neutralization method proposed in the Colombian Technical Norm 5473/07, by using a gel, alcoholbased disinfectant. Materials and methods. This study was done using Pseudomonas aeruginosa ATCC 15442, Staphylococcus aureus ATCC 6538, and Enterococcus hirae ATCC 10541 as the assay microorganisms. The study was carried out at 20±1°C as obligatory temperature and additionally at 36±1°C. Four contact times between microorganisms and the disinfectant were evaluated (0, 2, 5 and 10 minutes). The assay was done both under clean conditions (0.3 g/L of bovine serum albumin), and unclean conditions (3 g/L of bovine serum albumin and 3g/L of sheep erythrocytes). Results. The implementation of this method produced precise results in all of the six repetitions used during the assay. The obtained results demonstrated a logarithmic reduction higher than five, demonstrating the bactericidal activity exerted by the disinfectant on the control microorganisms. The established experimental conditions and methodology did not affect negatively the growth of any of the strains of microorganisms. Similarly, the neutralizing used did not inhibit the development of the microorganisms of the assay. Conclusions. The method was verified by means of the fulfillment of the limits set by the rule. Our results suggest that the method evaluated by means of the implementation of the protocol established in the Colombian Technical Norm 5473/07, allows evaluating the effectiveness of a disinfectant under selected and controlled experimental conditions. Key words: disinfection, clean conditions, unclean conditions, dilution-neutralization method, logarithmic reduction.

Download Full-text

Interaction of Bis-Guanidinium Acetates Surfactants with Bovine Serum Albumin Evaluated by Spectroscopy

Tenside Surfactants Detergents ◽

10.1515/tsd-2020-2283 ◽

2021 ◽

Vol 58 (3) ◽

pp. 187-194

Author(s):

Yongbo Song ◽

Yulan Niu ◽

Hongyan Zheng ◽

Ying Yao

Keyword(s):

Bovine Serum Albumin ◽

Serum Albumin ◽

Bovine Serum ◽

Cd Spectroscopy ◽

Binding Characteristics ◽

Low Concentrations ◽

Quenching Efficiency ◽

Hydrophobic Chain ◽

Upward Curvature ◽

High Concentrations

Abstract The interactions between cocopropane bis-guanidinium acetates, tallowpropane bis-guanidinium acetates with bovine serum albumin (BSA) in an aqueous solution were studied by fluorescence and circular dichroic spectroscopy measurements. The aim of the study was to elucidate the influence of the hydrophilic group and the length of the hydrophobic chain of these surfactants on the mechanism of binding to BSA. The results revealed that for both surfactants, at low concentrations, the Stern–Volmer plots had an upward curvature and at high concentrations, the quenching efficiency was decreased with increase in surfactant concentration. Different thermodynamics parameters demonstrated the existence of hydrogen bond and van der Waals force which acting as binding forces. Static quenching was observed among the protein and surfactant. The conformation of BSA was changed at higher surfactant concentrations as shown by synchronous fluorescence and CD spectroscopy. This work reveals the mechanism and binding characteristics between guanidine surfactants and protein, and provided the basis for further applications of surfactants.

Download Full-text

Albumin reduces basement membrane hydraulic conductance in part due to arginyl side groups

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1995.269.5.h1514 ◽

1995 ◽

Vol 269 (5) ◽

pp. H1514-H1521 ◽

Cited By ~ 1

Author(s):

M. A. Katz ◽

M. L. La Marche

Keyword(s):

Extracellular Matrix ◽

Bovine Serum Albumin ◽

Basement Membrane ◽

Serum Albumin ◽

Protective Effect ◽

Binding Sites ◽

Bovine Serum ◽

Hydraulic Conductance ◽

Experimental Control ◽

Low Concentrations

Albumin reduces capillary hydraulic conductance (Lp) even at low concentrations. To determine if part of this barrier protective effect might be extracellular, we studied the effects of bovine serum albumin (BSA) on Lp of self-assembled basement membrane (Matrigel). Lp with tris(hydroxymethyl)aminomethane (Tris) buffer superfusate was stable at 1.77 +/- 0.22 x 10(-5) (SE) cm.s-1.cmH2O-1 over several hours. At 0.1 g/dl BSA, experimental/control (Tris) Lp fell to 83.1 +/- 6.0% (2P < 0.025), with decreases to 72.4 +/- 3.7% at 1 g/dl (2P < 0.005), 45.3 +/- 5.1% at 2.5 g/dl (2P < 0.001), and 45.0 +/- 4.8% at 4.0 g/dl (2P < 0.001). In separate experiments, BSA arginine groups were neutralized by 1,2-cyclohexanedione (CHD), and experimental/control Lp values were measured. At 2.5 g/dl, CHD-BSA depressed Lp to 54.4 +/- 4.8%, while unmodified BSA reduced Lp to 40.8 +/- 3.5% of Tris control (2P = 0.05). Finally, soluble arginine at three- and sixfold the arginine in BSA was added to BSA superfusate. For threefold, Lp rose to 120 +/- 8% of BSA level and for sixfold to 129 +/- 9% (2P < 0.05). We conclude that some part of the albumin protective effect is very likely due to consequences on extracellular matrix and that at least 18-22% of this effect is related to arginine groups on albumin when computed from Lp, and up to 34% when viscosity is taken into account. Membrane-saturable arginine-binding sites can be unbound with arginine, thus nullifying part of the barrier protective effect of BSA.

Download Full-text