Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
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Target Concepts:
Gene/Protein
Disease
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Drug
Enzyme
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Query: UMLS:C0393754 (
HSA
)
2,996
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Total serum free fatty acids (FFAt) levels provide an important measure of the physiologic state. Most of the FFA in serum is bound to albumin; a small portion, however, is unbound. This study presents the first measurements of serum unbound free fatty acid (FFAu) concentrations. These measurements were made possible by the development of the fluorescence probe ADIFAB (acrylodated intestinal fatty acid binding protein). In the present study ADIFAB was shown to provide the correct value of the sum of the [FFAu] of each molecular species of
long chain
FFA: 1) in aqueous mixtures of FFA and ADIFAB; 2) in mixtures of FFA, human serum albumin, and ADIFAB; and 3) in serum and ADIFAB. Human serum [FFAu] were measured in 283 samples from healthy donors and yielded a mean value of 7.5 nM with a standard deviation of 2.5 nM. This measured value is as much as 1000-fold smaller than [FFAu] values previously estimated. The distribution of [FFAu] values was found to be invariant with donor gender and age. Average [FFAu] values do, as expected, exhibit a small (1.5 nM) but significant (P < 0.001) increase after overnight fasting. FFAu levels were found to be well correlated with total serum FFA or, equivalently, [FFAt]/[
HSA
]. Given their ease and accuracy, and because [FFAu] values increase exponentially with [FFAt]/[
HSA
], [FFAu] measurements could provide a sensitive method for assessing the physiologic state.
...
PMID:Unbound free fatty acid levels in human serum. 775 10
We present experimental evidence for the significant effect that water can have on the functional structure of proteins in solution. Human (
HSA
) and Bovine Serum Albumin (BSA) have an amino acid sequence identity of 75.52% and are chosen as model proteins. We employ EPR-based nanoscale distance measurements using double electron-electron resonance (DEER) spectroscopy and both albumins loaded with
long chain
fatty acids (FAs) in solution to globally (yet indirectly) characterize the tertiary protein structures from the bound ligands' points of view. The complete primary structures and crystal structures of
HSA
and as of recently also BSA are available. We complement the picture as we have recently determined the DEER-derived solution structure of
HSA
and here present the corresponding BSA solution structure. The characteristic asymmetric FA distribution in the crystal structure of
HSA
can surprisingly be observed by DEER in BSA in solution. This indicates that the BSA conformational ensemble in solution seems to be narrow and close to the crystal structure of
HSA
. In contrast, for
HSA
in solution a much more symmetric FA distribution was found. Thus, conformational adaptability and flexibility dominate in the
HSA
solution structure while BSA seems to lack these properties. We further show that differences in amino acid hydropathies of specific structural regions in both proteins can be used to correlate the observed difference in the global (tertiary) solution structures with the differences on the primary structure level.
...
PMID:Evidence for water-tuned structural differences in proteins: an approach emphasizing variations in local hydrophilicity. 2304 37
