Abstract：
:Type I DNA methyltransferases are complex multisubunit enzymes that methylate a specific base in each half of an asymmetric bipartite DNA recognition sequence. The specificity (S) subunit contains two corresponding DNA sequence recognition domains, plus a number of conserved regions which interact with two modification (M) subunits to form a trimeric enzyme of the form M2S. The way in which the subunits interact with DNA in a pseudo-symmetric fashion has long been unclear. Analysis of internal sequence repeats in the S-subunit shows the occurrence of significant homologies between the central conserved domain and sequences near the N and C termini. On the basis of this "split repeat", a "circular" organisation of the domains of this subunit is proposed that provides the required symmetry for interacting with the M-subunits and with the target DNA sequence. In the proposed model, one M-subunit interacts with the N and C-terminal conserved regions of the S-subunit, which are thereby brought into close proximity. The second M-subunit makes equivalent contacts with repeated sequences in the central conserved domain. The model suggests a more general scheme for the imposition of pseudo-dyad symmetry on protein subunits that have internal repeats by making equivalent contacts with additional subunits.
journal_name
J Mol Bioljournal_title
Journal of molecular biologyauthors
Kneale GGdoi
10.1006/jmbi.1994.1624subject
Has Abstractpub_date
1994-10-14 00:00:00pages
1-5issue
1eissn
0022-2836issn
1089-8638pii
S0022-2836(84)71624-Xjournal_volume
243pub_type
杂志文章,评审abstract：:The disulphide active sites of thioredoxin and DsbA are known to possess a high degree of structural homology. However, DsbA is a much stronger oxidant than thioredoxin. The redox potential difference between DsbA and thioredoxin has been measured to be 160 mV, equivalent to a shift of 15.4 kJ/mol in the reduced/oxidi...
journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1006/jmbi.1995.0303
更新日期：1995-06-02 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1006/jmbi.1995.0526
更新日期：1995-10-06 00:00:00
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pub_type： 杂志文章
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更新日期：2007-03-23 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：1986-04-05 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/j.jmb.2009.07.077
更新日期：2009-10-23 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：2014-03-06 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/0022-2836(91)90268-b
更新日期：1991-04-20 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：2008-02-22 00:00:00
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pub_type： 杂志文章
doi：10.1016/j.jmb.2005.01.061
更新日期：2005-03-25 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/j.jmb.2014.06.019
更新日期：2014-09-09 00:00:00
abstract：:The bacteriophage P1 recombinase Cre mediates site-specific recombination between loxP sites. The loxP site consists of two 13 base-pair inverted repeats separated by an eight base-pair spacer region. When DNA containing the loxP site is incubated with Cre, specific cleavages occur within the spacer region, creating a...
journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/0022-2836(85)90224-4
更新日期：1985-02-05 00:00:00
abstract：:A highly thermostable xylanase isolated from the thermophilic fungus Paecilomyces varioti has been crystallized by the vapour diffusion method. The isolation of this enzyme by crystallization directly from the culture filtrate projects this fungus as an important source for large-scale production of pure xylanase. The...
journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/0022-2836(94)90052-3
更新日期：1994-11-04 00:00:00
abstract：:Pulmonary surfactant protein D (SP-D) is a glycoprotein from the collectin family that is a component of the lung surfactant system. It exhibits host defense and immune regulatory functions in addition to contributing to the homeostasis of the surfactant pool within the alveolar airspaces. It is known that the SP-D mo...
journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/j.jmb.2018.03.027
更新日期：2018-05-11 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1006/jmbi.1996.0225
更新日期：1996-04-19 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：2009-07-24 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：1987-09-05 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/j.jmb.2005.07.064
更新日期：2005-09-30 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/j.jmb.2003.08.059
更新日期：2003-10-31 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/0022-2836(88)90387-7
更新日期：1988-01-05 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：1999-11-12 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：2008-04-25 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/j.jmb.2004.01.060
更新日期：2004-03-26 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1006/jmbi.2000.4002
更新日期：2000-08-18 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：2006-01-20 00:00:00
abstract：:Rat genomic clones, which together contain all of the rat genomic gamma-crystallin sequences, have been characterized. Five gamma-crystallin genes are located on a contiguous DNA region, 63 X 10(3) base-pairs long. These genes, named (5') gamma 1-1, gamma 1-2, gamma 2-2 and gamma 3-1 (3'), are all oriented head to tai...
journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/0022-2836(85)90201-3
更新日期：1985-04-05 00:00:00
abstract：:Sodium dodecyl sulfate (SDS) is a highly effective and widely used protein denaturant. We show that certain amphipathic cosolvents such as 2-methyl-2,4-pentanediol (MPD) can protect proteins from SDS denaturation, and in several cases can refold proteins from the SDS-denatured state. This cosolvent effect is observed ...
journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/j.jmb.2007.11.026
更新日期：2008-02-01 00:00:00
abstract：:The Clarke-Carbon library with Escherichia coli DNA cloned into plasmid ColE1 was partially screened for Z-DNA with the monoclonal antibody Z-D11 using the retardation of the covalently closed circular DNA-protein complex by nitrocellulose filters. About 85% of the plasmids tested at "natural" supercoil density bound ...
journal_title：Journal of molecular biology
pub_type： 杂志文章
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更新日期：1987-02-05 00:00:00
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journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/j.jmb.2005.11.074
更新日期：2006-03-31 00:00:00
abstract：:Translating ribosomes often stall during elongation. The stalled ribosomes are known to be recycled by tmRNA (SsrA)-mediated trans-translation. Another process that recycles the stalled ribosomes is characterized by peptidyl-tRNA release. However, the mechanism of peptidyl-tRNA release from the stalled ribosomes is no...
journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/j.jmb.2008.05.033
更新日期：2008-07-11 00:00:00
abstract：:Enzymes exhibit a strong long-range evolutionary constraint that extends from their catalytic site and affects even distant sites, where site-specific evolutionary rate increases monotonically with distance. While protein-protein sites in enzymes were previously shown to induce only a weak conservation gradient, a com...
journal_title：Journal of molecular biology
pub_type： 杂志文章
doi：10.1016/j.jmb.2019.07.019
更新日期：2019-09-06 00:00:00
