Abstract：
:Cytosine deaminase (CD) catalyzes the deamination of cytosine, producing uracil. This enzyme is present in prokaryotes and fungi (but not multicellular eukaryotes) and is an important member of the pyrimidine salvage pathway in those organisms. The same enzyme also catalyzes the conversion of 5-fluorocytosine to 5-fluorouracil; this activity allows the formation of a cytotoxic chemotherapeutic agent from a non-cytotoxic precursor. The enzyme is of widespread interest both for antimicrobial drug design and for gene therapy applications against tumors. The structure of Escherichia coli CD has been determined in the presence and absence of a bound mechanism-based inhibitor. The enzyme forms an (alphabeta)(8) barrel structure with structural similarity to adenosine deaminase, a relationship that is undetectable at the sequence level, and no similarity to bacterial cytidine deaminase. The enzyme is packed into a hexameric assembly stabilized by a unique domain-swapping interaction between enzyme subunits. The active site is located in the mouth of the enzyme barrel and contains a bound iron ion that coordinates a hydroxyl nucleophile. Substrate binding involves a significant conformational change that sequesters the reaction complex from solvent.
journal_name
J Mol Bioljournal_title
Journal of molecular biologyauthors
Ireton GC,McDermott G,Black ME,Stoddard BLdoi
10.1006/jmbi.2001.5277keywords:
subject
Has Abstractpub_date
2002-01-25 00:00:00pages
687-97issue
4eissn
0022-2836issn
1089-8638pii
S0022283601952775journal_volume
315pub_type
杂志文章abstract：:The gene sup61+, which codes for the essential Saccharomyces cerevisiae tRNA(SerUCG), is the only single-copy tRNA gene in this organism know to contain an intron. To assess the role of this intron in tRNA gene expression, an intron-deleted sup61+ gene was constructed in vitro and introduced into the yeast genome. Iso...
journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/0022-2836(88)90295-1
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abstract：:We identified the predominant 5' ends of an mRNA in Escherichia coli to the exact nucleotides. There are four such ends of lac mRNA in fully induced cells. About 70% of the molecules have the reported major in vitro end, A-A-U-U-G (at +1), which is located 38 nucleotides before the A-U-G translation start. Another 15%...
journal_title：Journal of molecular biology
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abstract：:alpha-Synuclein is an intrinsically disordered protein that appears in aggregated forms in the brains of patients with Parkinson's disease. The conversion from monomer to aggregate is complex, and aggregation rates are sensitive to changes in amino acid sequence and environmental conditions. It has previously been obs...
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pub_type： 杂志文章
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1006/jmbi.2001.4513
更新日期：2001-04-06 00:00:00
abstract：:The active sites of aspartate transcarbamoylase from Escherichia coli were titrated by measuring the decrease in the enzyme-catalyzed arsenolysis of N-carbamoyl-L-aspartate caused by the addition of the tight-binding inhibitor, N-phosphonacetyl-L-aspartate. Because the enzyme is a poor catalyst for this non-physiologi...
journal_title：Journal of molecular biology
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abstract：:Small, fast-growing bacteria make ideal subjects for genetic and quantitative analysis alike. Long the darling of theoreticians, efforts to understand the relationship between cell growth and cell cycle progression in bacterial systems have been propelled by modelers and empiricist in equal measure. Taking a historica...
journal_title：Journal of molecular biology
pub_type： 杂志文章,评审
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更新日期：2019-05-17 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
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更新日期：2005-06-17 00:00:00
abstract：:ThiI is an enzyme responsible for the formation of the modified base S(4)U (4-thiouridine) found at position 8 in some prokaryotic tRNAs. This base acts as a sensitive trigger for the response mechanism to UV exposure, providing protection against its damaging effects. We present the crystal structure of Bacillus anth...
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doi：10.1016/j.jmb.2005.11.013
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pub_type： 杂志文章
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pub_type： 杂志文章
doi：10.1016/j.jmb.2008.05.088
更新日期：2008-10-03 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/0022-2836(92)90624-s
更新日期：1992-08-05 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1006/jmbi.1996.0816
更新日期：1997-02-28 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1006/jmbi.2000.4224
更新日期：2000-12-01 00:00:00
abstract：:The mini-chromosome maintenance (MCM) complex is the presumptive replicative helicase in archaea and eukaryotes. In archaea, the MCM is a homo-multimer, in eukaryotes a heterohexamer composed of six related subunits, MCM 2-7. Biochemical studies using naked DNA templates have revealed that archaeal MCMs and a sub-comp...
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pub_type： 杂志文章
doi：10.1016/j.jmb.2006.01.074
更新日期：2006-04-14 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/j.jmb.2003.09.014
更新日期：2004-03-05 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/0022-2836(92)90553-v
更新日期：1992-04-05 00:00:00
abstract：:The prediction of protein-protein interactions in solution is a major goal of theoretical structural biology. Here, we implement a continuum description of the thermodynamic processes involved. The model differs considerably from previous models in its use of "molecular surface" area to describe the hydrophobic compon...
journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1006/jmbi.1995.0375
更新日期：1995-07-07 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
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更新日期：1991-10-05 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
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更新日期：1995-03-03 00:00:00
abstract：:Two crystal forms of hydroxypyruvate reductase (D-glycerate dehydrogenase) from the methylotrophic bacterium Hyphomicrobium methylovorum have been grown from ammonium sulphate solutions. One crystal form is triclinic, with unit cell parameters a = 60.4 A, b = 60.5 A, c = 66.3 A, alpha = 102.3 degrees, beta = 113.7 deg...
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pub_type： 杂志文章
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更新日期：1992-06-05 00:00:00
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pub_type： 杂志文章
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更新日期：1991-05-20 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
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更新日期：2007-09-21 00:00:00
abstract：:The Runt domain is the DNA binding domain of the core binding factor (CBF) Runx subunits. The CBFs are transcription factors that play critical roles in hematopoiesis, bone, and neuron development in mammals. A common non-DNA binding CBFbeta subunit heterodimerizes with the Runt domain of the Runx proteins and alloste...
journal_title：Journal of molecular biology
pub_type： 杂志文章
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