共查询到20条相似文献,搜索用时 31 毫秒
1.
Timothy S. Magnuson Michael W. Swenson Andrzej J. Paszczynski Lee A. Deobald David Kerk David E. Cummings 《Biometals》2010,23(6):1129-1138
Acidiphilium cryptum JF-5, an acidophilic iron-respiring Alphaproteobacterium, has the ability to reduce chromate under aerobic and anaerobic conditions, making it an intriguing and useful model organism for the study of extremophilic bacteria in bioremediation applications. Genome sequence annotation suggested two potential mechanisms of Cr(VI) reduction, namely, a number of c-type cytochromes, and a predicted NADPH-dependent Cr(VI) reductase. In laboratory studies using pure cultures of JF-5, an NADPH-dependent chromate reductase activity was detected primarily in soluble protein fractions, and a periplasmic c-type cytochrome (ApcA) was also present, representing two potential means of Cr(VI) reduction. Upon further examination, it was determined that the NADPH-dependent activity was not specific for Cr(VI), and the predicted proteins were not detected in Cr(VI)-grown cultures. Proteomic data did show measureable amounts of ApcA in cells grown with Cr(VI). Purified ApcA is reducible by menadiol, and in turn can reduce Cr(VI), suggesting a means to obtain electrons from the respiratory chain and divert them to Cr(VI). Electrochemical measurements confirm that Cr reduction by ApcA is pH dependent, with low pH being favored. Homology modeling of ApcA and comparison to a known Cr(VI)-reducing c-type cytochrome structure revealed basic amino acids which could interact with chromate ion. From these studies, it can be concluded that A. cryptum has the physiologic and genomic capability to reduce Cr(VI) to the less toxic Cr(III). However, the expected chromate reductase mechanism may not be the primary means of Cr(VI) reduction in this organism. 相似文献
2.
Marc Quinternet Laure Selme Chrystel Beaufils Pascale Tsan Christophe Jacob Sandrine Boschi-Muller Marie-Christine Averlant-Petit Guy Branlant Manh-Thong Cung 《Biomolecular NMR assignments》2008,2(1):85-87
We report the nearly complete 1H, 13C, and 15N resonance assignments of the C103S mutant of the N-terminal domain of DsbD from Neisseria meningitides. Secondary structure determination using CSI method leads to the prediction of nine β-sheet parts. 相似文献
3.
Backbone resonance assignment for the outer membrane lipoprotein receptor LolB from Escherichia coli
Shingo Nakada Masayoshi Sakakura Hideo Takahashi Hajime Tokuda Ichio Shimada 《Biomolecular NMR assignments》2007,1(1):121-123
LolB, which is anchored to the outer membrane of Gram-negative bacteria, receives outer-membrane-directed lipoproteins from
LolA, and incorporates them into the outer membrane. We established backbone resonance assignments of 2H/13C/15N labeled LolB from Escherichia coli. 相似文献
4.
Shingo Nakada Hideo Takahashi Masayoshi Sakakura Masuo Kurono Ichio Shimada 《Biomolecular NMR assignments》2007,1(1):125-127
LolA is an essential periplasmic protein in Gram-negative bacteria and plays a role in transporting lipoproteins through periplasmic
space from the inner to the outer membrane. We established backbone resonance assignments of 2H/13C/15N labeled LolA from Escherichia coli. 相似文献
5.
Marc Quinternet Chrystel Beaufils Fabrice Neiers Pascale Tsan Sandrine Boschi-Muller Marie-Christine Averlant-Petit Guy Branlant Manh-Thong Cung 《Biomolecular NMR assignments》2007,1(1):143-145
We report the nearly complete 1H, 13C and 15N resonance assignments of the oxidized form (Cys67–Cys70) of the N-terminal domain of PilB from Neisseria meningitidis. Secondary structure determination using CSI method and TALOS leads mainly to the prediction of 7 α-helical and 5 β-sheet
parts. 相似文献
6.
Lipocalin-type prostaglandin D synthase (L-PGDS) acts as both a PGD2-synthesizing enzyme and an extracellular transporter for small lipophilic molecules. Here we report the backbone and side-chain resonance assignments of uniformly 15N, 13C labeled rat L-PGDS. 相似文献
7.
The interaction between DnaG primase and DnaB helicase is essential for stimulating primer synthesis during bacterial DNA
replication. The interaction occurs between the N-terminal domain of helicase and the C-terminal domain of primase. Here we
present the 1H, 13C, and 15N backbone and side-chain resonance assignments for the C-terminal helicase interaction domain of Staphylococcus aureus primase. 相似文献
8.
Andreas Ioannis Karsisiotis Oliver M. Deacon Colin Macdonald Tharin M. A. Blumenschein Geoffrey R. Moore Jonathan A. R. Worrall 《Biomolecular NMR assignments》2017,11(2):165-168
Human cytochrome c plays a central role in the mitochondrial electron transfer chain and in the intrinsic apoptosis pathway. Through the interaction with the phospholipid cardiolipin, cytochrome c triggers release of pro-apoptotic factors, including itself, from the mitochondrion into the cytosol of cells undergoing apoptosis. The cytochrome c/cardiolipin complex has been extensively studied through various spectroscopies, most recently with high-field solution and solid-state NMR spectroscopies, but there is no agreement between the various studies on key structural features of cytochrome c in its complex with cardiolipin. In the present study, we report backbone 1H, 13C, 15N resonance assignments of acid-denatured human cytochrome c in the aprotic solvent dimethylsulfoxide. These have led to the assignment of a reference 2D 1H-15N HSQC spectrum in which out of the 99 non-proline residues 87% of the backbone amides are assigned. These assignments are being used in an interrupted H/D exchange strategy to map the binding site of cardiolipin on human cytochrome c. 相似文献
9.
《Bioscience, biotechnology, and biochemistry》2013,77(12):2052-2053
The conditions of cultivation and the composition of medium for Desulfovibrio vulgaris Miyazaki F (DvMF) were examined to obtain cytochrome c3 labeled with a stable isotope. The growth of DvMF was steady and reproducible under purging with N2 and under pH control. DvMF was able to grow on a defined medium without natural products. The composition of medium containing a small amount of NH4Cl as sole nitrogen source was established. Then, [U-15N]cytochrome c3 was obtained during the culture of DvMF in a defined medium with 15NH4Cl; it was confirmed by 1H?15N HMQC. This is the first report of [U-15N]cytochrome c3. 相似文献
10.
M. Rivera Feng Qiu Richard A. Bunce Ruth E. Stark 《Journal of biological inorganic chemistry》1999,4(1):87-98
Singly and doubly labeled δ-aminolevulinic acid derivatives were used to prepare rat liver outer mitochondrial membrane (OM)
cytochrome b
5 containing a 13C-labeled heme active site. A variety of NMR experiments, including HMBC and INADEQUATE in conjunction with the more commonly
used HMQC, NOESY, and COSY, were conducted to make unambiguous assignments of protonated carbons and the quaternary pyrrole-α
and -β carbons in both isomeric forms of the paramagnetic active center of OM cytochrome b
5. Because the long interpulse delays in the HMBC experiment have a detrimental effect on the detectability of fast relaxing
paramagnetically affected resonances, INADEQUATE is proposed as the experiment of choice for assigning quaternary carbons
in paramagnetic hemes with carefully chosen macrocycle labeling patterns. Furthermore, the applicability of the INADEQUATE
experiment to paramagnetic heme active sites should be facilitated greatly by the availability of biosynthetic methods for
producing isotopically labeled b-hemes and, more recently, isotopically labeled c-hemes.
Received: 21 September 1998 / Accepted: 25 November 1998 相似文献
11.
Hefke F Bagaria A Reckel S Ullrich SJ Dötsch V Glaubitz C Güntert P 《Journal of biomolecular NMR》2011,49(2):75-84
We present a computational method for finding optimal labeling patterns for the backbone assignment of membrane proteins and
other large proteins that cannot be assigned by conventional strategies. Following the approach of Kainosho and Tsuji (Biochemistry
21:6273–6279 (1982)), types of amino acids are labeled with 13C or/and 15N such that cross peaks between 13CO(i – 1) and 15NH(i) result only for pairs of sequentially adjacent amino acids of which the first is labeled with 13C and the second with 15N. In this way, unambiguous sequence-specific assignments can be obtained for unique pairs of amino acids that occur exactly
once in the sequence of the protein. To be practical, it is crucial to limit the number of differently labeled protein samples
that have to be prepared while obtaining an optimal extent of labeled unique amino acid pairs. Our computer algorithm UPLABEL
for optimal unique pair labeling, implemented in the program CYANA and in a standalone program, and also available through
a web portal, uses combinatorial optimization to find for a given amino acid sequence labeling patterns that maximize the
number of unique pair assignments with a minimal number of differently labeled protein samples. Various auxiliary conditions,
including labeled amino acid availability and price, previously known partial assignments, and sequence regions of particular
interest can be taken into account when determining optimal amino acid type-specific labeling patterns. The method is illustrated
for the assignment of the human G-protein coupled receptor bradykinin B2 (B2R) and applied as a starting point for the backbone assignment of the membrane protein proteorhodopsin. 相似文献
12.
The human ether à go-go related gene (hERG) voltage-gated potassium controls the rapid delayed rectifier potassium current (Iks) in heart. The N-terminal 135 amino acids (NTD) form a Per-Arnt-Sim (PAS) domain which involves in signal transduction and protein–protein interactions. NTD was shown to be necessary for the regulation of the channel activity through its interaction with the channel pore region of hERG. Mutations in NTD were related to serious heart diseases. We report the 1H, 13C and 15N chemical shift assignments for NTD using 2D and 3D heteronuclear NMR experiments. More than 95% backbone resonance assignments were obtained. 相似文献
13.
Robert M. G. Hynson Ann H. Kwan David A. Jacques Joel P. Mackay Jill Trewhella 《Biomolecular NMR assignments》2010,4(2):167-169
KipI is a sporulation inhibitor in Bacillus subtilis which acts by binding to the dimerisation and histidine phosphotransfer (DHp) domain of KinA, the principle input kinase in the phosphorelay responsible for sporulation. The 15N, 13C and 1H chemical shift assignments of the N-terminal domain of KipI were determined using multidimensional, multinuclear NMR experiments. The N-terminal domain has two conformers and resonance assignments have been made for both conformers. 相似文献
14.
Based on different characteristics between unlabeled and fully 15N,13C-labeled nucleotides, we develop a method for unambiguous resonance assignments in nucleic acids following site-specific fully 15N,13C isotope incorporation at very low levels1. The J-couplings between heteronuclei provide for distinction between the NMR signals of the fully labeled nucleotides and those of the natural abundance nucleotides. The method is demonstrated for DNA oligonucleotides2, in the dimeric G-quadruplex [d(GGGTTCAGG)]2and in the 22-nucleotide human telomeric fragment d[AG3(TTAG3)3]. We expect this approach to be useful for selective monitoring of important functional domains and of their interactions in large nucleic acids. 相似文献
15.
Protein splicing is a precise post-translational process mediated by inteins. Inteins are intervening proteins that cleave
themselves from a precursor protein while joining the flanking sequences. Here we report the 15N, 13C, and 1H chemical shift assignments of the intein from DNA polymerase II of Pyrococcus abyssi (Pab PolII intein), which has been recombinantly overexpressed and isotopically labeled. The NMR assignments of Pab PolII intein are essential for solution structure determination and protein dynamics study. 相似文献
16.
Raf-1 kinase inhibitor protein (RKIP) plays a pivotal role in modulating multiple signaling networks. Here we report backbone
and side chain resonance assignments of uniformly 15N, 13C labeled human RKIP. 相似文献
17.
Kobayashi H Swapna GV Wu KP Afinogenova Y Conover K Mao B Montelione GT Inouye M 《Journal of biomolecular NMR》2012,52(4):303-313
A common obstacle to NMR studies of proteins is sample preparation. In many cases, proteins targeted for NMR studies are poorly
expressed and/or expressed in insoluble forms. Here, we describe a novel approach to overcome these problems. In the protein
S tag-intein (PSTI) technology, two tandem 92-residue N-terminal domains of protein S (PrS2) from Myxococcus xanthus is fused at the N-terminal end of a protein to enhance its expression and solubility. Using intein technology, the isotope-labeled
PrS2-tag is replaced with non-isotope labeled PrS2-tag, silencing the NMR signals from PrS2-tag in isotope-filtered 1H-detected NMR experiments. This method was applied to the E. coli ribosome binding factor A (RbfA), which aggregates and precipitates in the absence of a solubilization tag unless the C-terminal
25-residue segment is deleted (RbfAΔ25). Using the PrS2-tag, full-length well-behaved RbfA samples could be successfully prepared for NMR studies. PrS2 (non-labeled)-tagged RbfA (isotope-labeled) was produced with the use of the intein approach. The well-resolved TROSY-HSQC
spectrum of full-length PrS2-tagged RbfA superimposes with the TROSY-HSQC spectrum of RbfAΔ25, indicating that PrS2-tag does not affect the structure of the protein to which it is fused. Using a smaller PrS-tag, consisting of a single N-terminal
domain of protein S, triple resonance experiments were performed, and most of the backbone 1H, 15N and 13C resonance assignments for full-length E. coli RbfA were determined. Analysis of these chemical shift data with the Chemical Shift Index and heteronuclear 1H–15N NOE measurements reveal the dynamic nature of the C-terminal segment of the full-length RbfA protein, which could not be
inferred using the truncated RbfAΔ25 construct. CS-Rosetta calculations also demonstrate that the core structure of full-length
RbfA is similar to that of the RbfAΔ25 construct. 相似文献
18.
Chung-Kyung Lee Kwon Joo Yeo Eunha Hwang Hae-Kap Cheong 《Biomolecular NMR assignments》2013,7(1):89-92
Angiogenin is an unusual member of the pancreatic ribonuclease superfamily that induces formation of new blood vessels and is a promising anti-cancer target. Here we report backbone and side chain 1H, 13C, and 15N resonance assignments for rat angiogenin (residues 24–145), excluding the N-terminal signal peptide. These data allow nuclear magnetic resonance structure and inhibitor-binding studies with the aim of providing angiogenin antagonists as potential therapeutics. 相似文献
19.
Michal Respondek Lieven Buts Natalie De Jonge Sarah Haesaerts Remy Loris Laurence Van Melderen Lode Wyns Klaus Zangger 《Biomolecular NMR assignments》2009,3(1):145-147
CcdB is the toxic component of a bacterial toxin–antitoxin system. It inhibits DNA gyrase (a type II topoisomerase), and its
toxicity can be neutralized by binding of its antitoxin CcdA. Here we report the sequential backbone and sidechain 1H, 15N and 13C resonance assignments of CcdBVfi from the marine bacterium Vibrio fischeri. The BMRB accession number is 16135. 相似文献
20.
An N-terminally modified form of the Arabidopsis NADPH–cytochrome P450 ATR2 (ATR2mod) was expressed from the tactac promoter in Escherichia coli to obtain high yields of the enzyme. The N-terminal modification eliminates the predicted chloroplast transit peptide of ATR2 allowing for more efficient expression. ATR2mod was purified from membrane extracts using a 2′,5′-ADP–agarose affinity column. The specific activity of the purified ATR2mod for cytochrome c reduction was 9.4 μmol min−1 mg−1 and the Km for cytochrome c reduction was 15 ± 2 μM. The purified NADPH–cytochrome P450 reductase was able to support function of CYP79B2. 相似文献