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

Receptor-mediated binding of leukocyte chemotactic peptide, N-formylMet-Leu-Phe (fMLP), occurs in the ciliated protozoon Tetrahymena thermophila. In vivo labelling of the cells with N-formylMet-Leu-[3H]Phe ([3H]fMLP) shows that the cells bind the ligand with high affinity (KD = 4 × 10(−9) M to 1 × 10(−8) M). Moreover, Scatchard transformations of the binding data show that there are about 5 × 10(5) binding sites per cell on the cell surface. Two fluorescent derivatives of leukocyte chemotactic peptide, N-dansylMet-Leu-Phe (dansMLP) and N-formylMet-Leu-Phe-(N-dansyl-)Lys (fMLPdanLys) compete for the N-formylMet-Leu-Phe (fMLP) binding sites on the cell surface. Moreover, both derivatives have retained significant chemoattracting potentials. Fluorescence from dansMLP, but not from fMLPdansLys and dansyl-beta-endorphin, is internalized preferentially into small vesicles. The differences may, however, reflect that the fluorescence from the dansyl group is strongly quenched by a hydrophilic microenvironment when using the two latter peptide derivatives. In contrast, the dansyl group from dansMLP must be assumed to be embedded in a hydrophobic microenvironment in the vesicular membrane or membrane protein. Rhodamine-labelled bovine serum albumin, egg albumin and cytochrome c as well as dansylated bovine serum albumin, which are poor chemoattractants, are preferentially seen to be internalized into large vesicles (food vacuoles).

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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.

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Identification of macrophage cell-surface binding sites for cationized bovine serum albumin

Biochemical and Biophysical Research Communications ◽

10.1016/0006-291x(91)91259-f ◽

1991 ◽

Vol 181 (2) ◽

pp. 787-796 ◽

Cited By ~ 12

Author(s):

Jan G. Dohlman ◽

Dennis J. Pillion ◽

Luis A. Rokeach ◽

M.P. Ramprasad

Keyword(s):

Bovine Serum Albumin ◽

Cell Surface ◽

Serum Albumin ◽

Binding Sites ◽

Bovine Serum ◽

Surface Binding ◽

Macrophage Cell ◽

Cell Surface Binding

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Dilation of intracerebral arterioles in vitro by fatty acid contamination in bovine serum albumin

Microvascular Research ◽

10.1016/0026-2862(87)90059-8 ◽

1987 ◽

Vol 34 (2) ◽

pp. 256-259 ◽

Cited By ~ 4

Author(s):

John E. Bassett ◽

Ralph G. Dacey

Keyword(s):

Fatty Acid ◽

Bovine Serum Albumin ◽

Serum Albumin ◽

Bovine Serum

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

Biochemical Journal ◽

10.1042/bj2500477 ◽

1988 ◽

Vol 250 (2) ◽

pp. 477-484 ◽

Cited By ~ 28

Author(s):

R P Hafner ◽

M D Brand

Keyword(s):

Fatty Acid ◽

Bovine Serum Albumin ◽

Serum Albumin ◽

Adenylate Kinase ◽

Bovine Serum ◽

Mitochondrial Protein ◽

Experimental Conditions ◽

Low Concentrations ◽

The Difference

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.

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