Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Fluorescence Quenching of Alpha-Fetoprotein by Gold Nanoparticles: Effect of Dielectric Shell on Non-Radiative Decay
Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học General Psychiatry cung cấp cho các bạn kiến thức về ngành y đề tài: Assessment of tissue oxygen tension: comparison of dynamic fluorescence quenching and polarographic electrode technique...
We have used fluorescence quench titrations, EPR spectroscopy and
steady-state kinetics to study the effects of site-directed mutants of FrdB,
FrdC and FrdD on the proximal menaquinol (MQH2) binding site (QP)of
Escherichia colifumarate reductase (FrdABCD) in cytoplasmic membrane
preparations. Fluorescence quench (FQ) titrations with the fluorophore
analog 2-n-heptyl-4-hydroxyquinoline-N-oxide (HOQNO) indi-cate that the QPsite is defined by residues from FrdB, FrdC and FrdD. In
FQ titrations, wild-type FrdABCD binds HOQNO with an apparentKdof
Biophotonics is revolutionizing the field of medicine, biology and
chemistry and creating a new breed of medical engineers while at the
same time getting engineers a taste of medicine. From an engineer's
perspective, biophotonics is the application of photonics - the technology
of generating and harnessing packet of light energy called photons - to
image, detect and manipulate biological materials. In biology the
understanding of molecular mechanisms, function of proteins and
molecules has seen great new advances.
This introduction to Evidence-Based Dentistry provides a much-needed orientation in the subject for students and professionals alike. It is a ground-level book for those seeking to understand evidence-based dentistry and its significance for clinical practice. The book is anchored in the dental literature: the majority of the chapters offer guidance on interpreting a full published paper; where both the subject of the paper and the study design is of relevance to the field of dentistry.
The binding of Thermomyces lanuginosa lipase and its mutants [TLL(S146A), TLL(W89L), TLL(W117F, W221H, W260H)] to the mixed micelles of cis-parinaric acid/ sodium taurodeoxycholate at pH 5.0 led to the quenching of the intrinsic tryptophan ﬂuorescence emission (300–380 nm) and to a simultaneous increase in the cis-parinaric acid ﬂuorescence emission (380–500 nm). These ﬁndings were used to characterize the Thermomyces lanuginosa lipase/cisparinaric acid interactions occurring in the presence of sodium taurodeoxycholate....
A molecular understanding of volatile anesthetic mechanisms of action will
require structural descriptions of anesthetic–protein complexes. Porcine
odorant binding protein is a 157 residue member of the lipocalin family
that features a large b-barrel internal cavity (515 ± 30 A
) lined predomin-antly by aromatic and aliphatic residues. Halothane binding to theb-barrel
cavity was determined using fluorescence quenching of Trp16, and a com-petitive binding assay with 1-aminoanthracene.
The structural properties of EspB, a virulence factor of theEscherichia coli
O157 type III secretion system, were characterized. Far-UV and near-UV
CD spectra, recorded between pH 1.0 and pH 7.0, show that the protein
assumesa-helical structures and that some tyrosine tertiary contacts may
exist. All tyrosine side-chains are exposed to water, as determined by acryl-amide fluorescence quenching spectroscopy.
Cyclic AMP receptor protein (CRP) regulates the expression of more then
100 genes inEscherichia coli. It is known that the allosteric activation of
CRP by cAMP involves a long-distance signal transmission from the N-ter-minal cAMP-binding domain to the C-terminal domain of CRP responsible
for the interactions with specific sequences of DNA. In this report we have
used a CRP mutant containing a single Trp13 located in the N-terminal
domain of the protein.
Recent crosslinking studies indicated the localization of
the coupling ion binding site in the Na
ATP synthase ofIlyobacter tartaricus within the
hydrophobic part of the bilayer.Similarly, a membrane
-binding site is accepted for the H
-trans-locating F1F0 ATP synthase ofEscherichia coli.For a
more definite analysis, we performed parallax analysis of
fluorescence quenching with ATP synthases from both
I. tartaricus and E. coli.
The recombinant cysteine peptidases, cruzain from
Trypanosoma cruziand CPB2.8DCTE fromLeishmania
mexicana, are cathepsin L-like and characteristically endo-peptidases. In this study, we characterized the carboxydi-peptidase activities of these enzymes and compared them
with those of human recombinant cathepsin B and cathep-sin L. The analysis used the internally quenched fluorescent
peptide Abz-FRFK*-OH and some of its analogues, where
Abz isortho-aminobenzoic acid and K* is (2,4-dinitrophe-nyl)-e-NH2-lysine. ...
Intravenous iron, used for the treatment of anemia in
chronic renal failure andother diseases, represents a possible
source of free iron in tissue cells, particularly in the liver. In
this study we examined the effect of different sources of
intravenous iron (IVI) on the labile iron pool (LIP) which
represents the nonferritin-bound, redox-active iron that is
implicated in oxidative stress and cell injury. Furthermore,
we examined the role of the LIP for the synthesis of ferritin.
We report the recombinant neurolysin and thimet oligo-peptidase (TOP) hydrolytic activities towards internally
quenched fluorescent peptides derived from the peptide
EDDnp,N-(2,4-dinitrophenyl) ethylenediamine), in which
X was substituted by 11 different natural amino acids.
Neurolysin hydrolyzed these peptides at R–R or at R–X
bonds, and TOP hydrolyzed at R–R or L–R bonds,
showing a preference to cleave at three or four amino
acids from the C-terminal end. ...