Abstract:
:Light-induced hypsochromic shifts of the Q(y) absorption band of the bacteriochlorophyll dimer (P) from 865 to 850 nm were identified using continuous illumination of dark-adapted reaction centers (RCs) from Rhodobacter capsulatus when dispersed in the most commonly used detergent, the zwitterionic lauryl N-dimethylamine-N-oxide. Such a shift is known to be the consequence of the decreased degree of delocalization of P. A 2-fold acceleration of the recovery kinetics of P(+) was found in RCs that underwent light-induced structural changes compared to those where the P-band position did not change. The light-induced shift was irreversible except in the presence of a secondary electron donor. Prolonged (15 min) illumination resulted in a shift in the position of the P-band even in neutral or negatively charged detergents. In contrast, RCs reconstituted into liposomes made from lipids with different headgroup charges showed light-induced shifts only if shorter fatty acid chains were used. The light-induced conformational changes caused a prominent decrease of the redox potential of P ranging from 120 to 160 mV depending on the detergent compared to the potential of P in dark-adapted reaction centers. The measured light-induced potential decreases were 55 to 85 mV larger than those reported for reaction centers where the P-band position remained at 865 nm. The influence of structural factors, such as the delocalization of the electron hole on P(+), the involvement of Tyr M210, and the hydrophobic mismatch between the thickness of the hydrophobic belt of the detergent micelles or the lipid bilayer and the RC protein, on the spectral features and electron transfer kinetics is discussed.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Deshmukh SS,Akhavein H,Williams JC,Allen JP,Kalman Ldoi
10.1021/bi200595zsubject
Has Abstractpub_date
2011-06-14 00:00:00pages
5249-62issue
23eissn
0006-2960issn
1520-4995journal_volume
50pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::Using 125I-labeled phenol-alanine sparsomycin, an analogue of sparsomycin having higher biological activity than the unmodified antibiotic, we studied the requirements and the characteristics of its interaction with the ribosome. The drug does not bind to either isolated ribosomal subunits or reconstituted whole ribos...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00104a011
更新日期:1991-10-08 00:00:00
abstract::The effect of both antimitotic drugs and nucleotide analogues on the magnesium-induced self-association of purified tubulin into 42S double rings has been examined by sedimentation velocity. In the absence of magnesium, all complexes sedimented as the 5.8S species. The binding of colchicine to tubulin led to a small b...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00149a044
更新日期:1992-09-01 00:00:00
abstract::Volumetric characteristics of protein recognition events determine the direction of pressure-induced shifts in the recognition reaction, while also providing insights into the structural, dynamic, and hydration changes. We report changes in volume, ΔV, and adiabatic compressibility, ΔK(S), accompanying the binding of ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi3006994
更新日期:2012-07-24 00:00:00
abstract::The heterotrimeric G protein subunit, alpha(s), can move reversibly from plasma membranes to cytoplasm in response to activation by GPCRs or activating mutations. We examined the importance of the unique N-terminus of alpha(s) in this translocation in cultured cells. alpha(s) contains a single site for palmitoylation ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi025533u
更新日期:2002-07-30 00:00:00
abstract::Many investigations have revealed that ribosome numbers increase in parallel with the growth rate of cells. Here we show that the absolute level of protein synthesis may not be the only factor influencing rRNA synthesis in a nondividing eukaryotic cell. Under conditions of complete (greater than 99%) inhibition of pro...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00502a003
更新日期:1990-12-18 00:00:00
abstract::Maltosyl isothiocyanate (MITC) has been synthesized from maltose with an overall yield of 88%. It has been found to be a potent irreversible inhibitor of zero trans influx of glucose with human erythrocytes. Kinetic analysis of glucose transport after treatment of erythrocytes with MITC revealed that VT was diminished...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00547a025
更新日期:1980-03-18 00:00:00
abstract::A novel inhibitor of p38 mitogen-activated protein kinase (p38), CMPD1, identified by high-throughput screening, is characterized herein. Unlike the p38 inhibitors described previously, this inhibitor is substrate selective and noncompetitive with ATP. In steady-state kinetics experiments, CMPD1 was observed to preven...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0495073
更新日期:2004-09-21 00:00:00
abstract::Trinucleotide repeat expansion diseases (TREDs) are correlated with elongation of CNG DNA and RNA repeats to pathological level. This paper shows, for the first time, complete data concerning thermodynamic stabilities of RNA with CNG trinucleotide repeats. Our studies include the stability of oligoribonucleotides comp...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0502339
更新日期:2005-08-16 00:00:00
abstract::Lipidic membrane systems that have been reported to be composed of sphingomyelin (SM)-cholesterol (Chol) microdomains or "rafts" by Dietrich et al. [palmitoyloleoyl-phosphatidylcholine(POPC)/SM/Chol, 1/1/1; Dietrich, C., Bagatolli, L. A., Volovyk, Z. N., Thompson, N. L., Levi, M., Jacobson, K., and Gratton, E. (2001) ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi026717b
更新日期:2003-02-18 00:00:00
abstract::We investigated the molecular mechanisms and the binding site location for the fluorophor crystal violet (CrV), a noncompetitive antagonist of the nicotinic acetylcholine receptor (AChR). To this end, radiolabeled competition binding, fluorescence spectroscopy, Schild-type analysis, patch-clamp recordings, and molecul...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi051752e
更新日期:2006-02-21 00:00:00
abstract::High-risk human papillomavirus E6 participates in tumorigenic progression, mainly by its ability to promote p53 degradation. HPV transcripts show a complex splicing pattern, where E6* is the most abundant transcript in high-risk HPV types, comprising the first 50 amino acids of E6. No structural or biochemical informa...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi101941c
更新日期:2011-03-01 00:00:00
abstract::Chlorophyll a fluorescence emission is widely used as a noninvasive measure of a number of parameters related to photosynthetic efficiency in oxygenic photosynthetic organisms. The most important component for the estimation of photochemistry is the relative increase in fluorescence yield between dark-adapted samples ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9806854
更新日期:1998-08-04 00:00:00
abstract::The glucose derivative, 2,2,6,6-tetramethylpiperidine-1-oxylglucose (TEMPO-glucose) was synthesized and examined for its ability to substitute for glucose as a substrate for the intestinal brush border membrane Na+/glucose cotransporter. TEMPO-glucose inhibited Na(+)-dependent phlorizin binding with an apparent KI of ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00231a012
更新日期:1991-04-30 00:00:00
abstract::The complete coordination scheme for Mn(II) in transition-state-analogue complexes with creatine kinase has been determined by electron paramagnetic resonance (EPR) spectroscopy. Perturbations in the EPR spectra for Mn(II) due to superhyperfine coupling to 17O of selectively labeled ligands have been used to identify ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00565a002
更新日期:1980-11-25 00:00:00
abstract::We investigated how the intrinsic sequence-dependent properties probed via the phosphate linkages (BI ↔ BII equilibrium) influence the preferred shape of free DNA, and how this affects the nucleosome formation. First, this exploits NMR solution studies of four B-DNA dodecamers that together cover 39 base pairs of the ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi500504y
更新日期:2014-09-09 00:00:00
abstract::The binding of ethidium bromide to the self-complementary deoxytetranucleotides containing guanine and cytosine bases has been studied by circular dichroism, visible absorption, and fluorescence spectroscopies. The circular dichroism spectrum of each of the four deoxytetranucleotides was measured and compared to the s...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00616a002
更新日期:1978-11-14 00:00:00
abstract::The conformation of two fragments derived from anti-poly(D-alanyl) antibodies, the divalent fragment (Fab')2 and the monovalent fragment Fab', was studied by small-angle X-ray scattering before and after interaction with the tetra-D-alanine amide hapten. More than 90% of the combining sites were occupied by the hapten...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00677a035
更新日期:1975-03-25 00:00:00
abstract::Purified subunits of intermediate filaments obtained from a variety of tissues and cell types contain O-phosphoserine and, in some cases, smaller amounts of O-phosphothreonine. The O-phosphoserine content was estimated by reaction of performic acid oxidized subunits with methylamine in NaOH. Decamin of BHK-21 and CHO ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00530a030
更新日期:1982-01-05 00:00:00
abstract::Following a 1-h [3H]uridine pulse of cells of a human colon carcinoma line, 15% of the radioactivity in heterogeneous nuclear RNA associated with both chromatin and nuclear ribonucleoprotein was not digested to acid soluble fragments during a 2-h incubation with staphylococcal nuclease (EC 3.1.4.7). These [3H]uridine-...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00662a026
更新日期:1976-08-24 00:00:00
abstract::The essential prokaryotic cell division protein FtsZ is a tubulin homologue that forms a ring at the division site. FtsZ forms polymers in a GTP-dependent manner. Recent biochemical evidence has shown that FtsZ forms multimeric structures in vitro and in vivo and functions as a self-activating GTPase. Structural analy...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi011370i
更新日期:2002-01-15 00:00:00
abstract::A 15-residue fragment within the major continuous domain of gp120 from HIV-1 that can bind independently to the CD4 receptor has been shown to have the property of behaving as a solvent polarity-dependent conformational switch. The switch behavior (cooperative transition from beta-sheet to helical conformation as a fu...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi952045w
更新日期:1996-01-16 00:00:00
abstract::Type II topoisomerases are responsible for DNA unlinking during DNA replication and chromosome segregation. Although eukaryotic enzymes are homodimers and prokaryotic enzymes are heterotetramers, both prokaryotic and eukaryotic type II topoisomerases belong to a single protein family. The amino- and carboxyl-terminal ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0155201
更新日期:2001-07-24 00:00:00
abstract::Despite the expression of only one type of receptor, there is great variation in the ability of different cell types to discriminate between C5a and its more stable metabolite, C5a des Arg74. The mechanism that underlies this phenomenon is not understood but presumably involves differences in the interaction with the ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi990139q
更新日期:1999-07-27 00:00:00
abstract::Vinca site agents are antimicrotubule compounds that bind to the same site on tubulin as do the vinca alkaloids. These include agents that induce the formation of nonmicrotubule oligomers of tubulin (vinblastine and vincristine) and agents that do not (maytansine and rhizoxin). All of these quench the fluorescence of ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00021a012
更新日期:1995-05-30 00:00:00
abstract::Mixtures of 1,2-dipalmitoylglycerol (1,2-DPG), 1,2-dioleylglycerol (1,2-DOG), 1,2-dicapryloylglycerol (1,2-DCG), 1,3-dioleylglycerol (1,3-DOG), and 1,3-dicapryloylglycerol (1,3-DCG) with dipalmitoylphosphatidylcholine (DPPC) have been studied by means of differential scanning calorimetry (DSC) and fluorescence depolar...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00425a022
更新日期:1988-12-13 00:00:00
abstract::The properties of a series of new potentiometric membrane probes have been explored. The probes all contain an (aminostyryl)pyridinium chromophore or a more highly conjugated analogue. The spectral properties of the dyes are discussed in terms of the excitation-induced charge shift from the pyridine to the aniline; th...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00342a010
更新日期:1985-10-08 00:00:00
abstract::The calcium-dependent interaction of several annexins with membranes was studied. A novel technique was developed that allowed estimation of calcium binding to aggregating systems. This consisted of immobilized phospholipids on phenyl-Sepharose. Proteins associated with this affinity gel in the presence of radioactive...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00249a009
更新日期:1994-11-15 00:00:00
abstract::Penicillin-binding protein 5 (PBP 5) from Escherichia coli is a well-characterized d-alanine carboxypeptidase that serves as a prototypical enzyme to elucidate the structure, function, and catalytic mechanism of PBPs. A comprehensive understanding of the catalytic mechanism underlying d-alanine carboxypeptidation and ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0473004
更新日期:2005-06-14 00:00:00
abstract::Probing and interrogating protein interactions that involve acyl carrier proteins (ACP's) in fatty acid synthases and polyketide synthases are critical to understanding the molecular basis for the programmed assembly of complex natural products. Here, we have used unnatural amino acid mutagenesis to site specifically ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi500936u
更新日期:2014-12-09 00:00:00
abstract::Caveolae are approximately 50-100 nm invaginations of the plasma membrane thought to form as a result of a local accumulation of cholesterol, sphingolipids, and a unique family of three proteins known as the caveolins: Cav-1, -2, and -3. Here, we report the identification, sequence, and developmental expression of the...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi020043n
更新日期:2002-06-25 00:00:00