Abstract:
:The time-course of synthesis of long and short (abortive) transcripts by Escherichia coli RNA polymerase was investigated under single round conditions in vitro. The synthesis of long RNA initiated at the lambda PR (with an altered leader sequence) or at the lacUV5 promoter was completed within five minutes, but abortive transcripts were continuously synthesized for at least 20 minutes. The results indicate the presence of transcription complexes that are capable only of abortive synthesis, and not of productive elongation. Consistently, only one in four of the RNA polymerase molecules that initially associated with the lambda PR promoter synthesized long RNA. The enzyme reisolated from productive complexes synthesized both long and abortive transcripts, behaving just like the original enzyme. This suggests that RNA polymerase is homogeneous with respect to its ability to synthesize the two types of product. Overall, the results indicate that many transcription complexes can be irreversibly trapped in vitro in an abortive cycle.
journal_name
J Mol Bioljournal_title
Journal of molecular biologyauthors
Kubori T,Shimamoto Ndoi
10.1006/jmbi.1996.0100subject
Has Abstractpub_date
1996-03-01 00:00:00pages
449-57issue
3eissn
0022-2836issn
1089-8638pii
S0022-2836(96)90100-Xjournal_volume
256pub_type
杂志文章abstract::Transcript elongation factor TFIIS promotes efficient transcription by RNA polymerase II, since it assists in bypassing blocks during mRNA synthesis. While yeast cells lacking TFIIS are viable, inactivation of mouse TFIIS causes embryonic lethality. Here, we have identified a protein encoded in the Arabidopsis genome ...
journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1016/j.jmb.2008.12.066
更新日期:2009-02-27 00:00:00
abstract::HscA, a specialized bacterial Hsp70-class molecular chaperone, interacts with the iron-sulfur cluster assembly protein IscU by recognizing a conserved LPPVK sequence motif. We report the crystal structure of the substrate-binding domain of HscA (SBD, residues 389-616) from Escherichia coli bound to an IscU-derived pep...
journal_title:Journal of molecular biology
pub_type: 杂志文章
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更新日期:2004-09-24 00:00:00
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journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1006/jmbi.1998.2162
更新日期:1998-11-20 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:2014-02-06 00:00:00
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journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1006/jmbi.1994.1591
更新日期:1994-09-30 00:00:00
abstract::The telomeric d(GGGGTT).d(AACCCC) repeat tracts (G4T2 repeats) in Tetrahymena thermophila macronuclei were shown previously to be packaged in a non-nucleosomal DNA-protein complex. Here, we demonstrate that these telomeric repeats, together with a short region of the immediately adjacent non-telomeric sequence, exist ...
journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1006/jmbi.1998.1867
更新日期:1998-07-17 00:00:00
abstract::Computational searches for DNA binding sites often utilize consensus sequences. These search models make assumptions that the frequency of a base pair in an alignment relates to the base pair's importance in binding and presume that base pairs contribute independently to the overall interaction with the DNA-binding pr...
journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1016/j.jmb.2008.04.043
更新日期:2008-06-20 00:00:00
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journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1016/j.jmb.2014.04.028
更新日期:2014-07-15 00:00:00
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pub_type: 杂志文章
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更新日期:2000-08-18 00:00:00
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pub_type: 杂志文章
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更新日期:2016-07-31 00:00:00
abstract::Membranes have a potent ability to promote secondary structure formation in a wide range of membrane-active peptides, believed to be due to a reduction through hydrogen bonding of the energetic cost of partitioning peptide bonds. This process is of fundamental importance for understanding the mechanism of action of to...
journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1006/jmbi.1998.2346
更新日期:1999-01-29 00:00:00
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journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1016/j.jmb.2006.04.001
更新日期:2006-06-16 00:00:00
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journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:
更新日期:2010-08-13 00:00:00
abstract::As regulators of ubiquitous biological processes, serine proteases can cause disease states when inappropriately expressed or regulated, and are thus rational targets for inhibition by drugs. Recently we described a new inhibition mechanism applicable for the development of potent, selective small molecule serine prot...
journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1006/jmbi.1999.3071
更新日期:1999-09-24 00:00:00
abstract::The ability of homologous chromosomes (or selected chromosomal loci) to pair specifically in the apparent absence of DNA breakage and recombination represents a prominent feature of eukaryotic biology. The mechanism of homology recognition at the basis of such recombination-independent pairing has remained elusive. A ...
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pub_type: 杂志文章,评审
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更新日期:2020-02-07 00:00:00
abstract::Protein engineering experiments and Phi(F)-value analysis of SH3 domains reveal that their transition state ensemble (TSE) is conformationally restricted, i.e. the fluctuations in the transition state (TS) structures are small. In the TS of src SH3 and alpha-spectrin SH3 the distal loop and the associated hairpin are ...
journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1006/jmbi.2002.5453
更新日期:2002-04-12 00:00:00
abstract::Bacterial microcompartments (BMCs) sequester enzymes from the cytoplasmic environment by encapsulation inside a selectively permeable protein shell. Bioinformatic analyses indicate that many bacteria encode BMC clusters of unknown function and with diverse combinations of shell proteins. The genome of the halophilic m...
journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1016/j.jmb.2014.02.025
更新日期:2014-05-29 00:00:00
abstract::Mutants of an archaeon Halobacterium halobium, resistant to the universal inhibitor of translation, pactamycin, were isolated. Pactamycin resistance correlated with the presence of mutations in the 16 S rRNA gene of H. halobium single rRNA operon. Three types of mutations were found in pactamycin resistant cells, A694...
journal_title:Journal of molecular biology
pub_type: 杂志文章,评审
doi:10.1006/jmbi.1997.1387
更新日期:1997-11-21 00:00:00
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journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1016/j.jmb.2005.11.046
更新日期:2006-02-24 00:00:00
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journal_title:Journal of molecular biology
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abstract::Phosphofructokinase-1 and -2 (Pfk-1 and Pfk-2, respectively) from Escherichia coli belong to different homologous superfamilies. However, in spite of the lack of a common ancestor, they share the ability to catalyze the same reaction and are inhibited by the substrate MgATP. Pfk-2, an ATP-dependent 6-phosphofructokina...
journal_title:Journal of molecular biology
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journal_title:Journal of molecular biology
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doi:10.1006/jmbi.1999.3445
更新日期:2000-02-04 00:00:00
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journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1006/jmbi.1999.2916
更新日期:1999-07-16 00:00:00
abstract::Proteins and synthetic polymers can undergo phase transitions in response to changes to intensive solution parameters such as temperature, proton chemical potentials (pH), and hydrostatic pressure. For proteins and protein-based polymers, the information required for stimulus-responsive phase transitions is encoded in...
journal_title:Journal of molecular biology
pub_type: 杂志文章,评审
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更新日期:2018-11-02 00:00:00
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journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1016/j.jmb.2006.10.011
更新日期:2007-01-12 00:00:00
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journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1016/j.jmb.2013.05.006
更新日期:2013-10-23 00:00:00
abstract::Src homology-2 (SH2) domains are protein modules found within a wide variety of cytoplasmic signalling molecules that bind with high affinity to phosphotyrosyl-containing protein sequences. In order to develop SH2 inhibitors that contain phosphotyrosyl analogues resistant to cellular phosphatases, we have solved the c...
journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1006/jmbi.1994.0089
更新日期:1995-02-17 00:00:00
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journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1016/j.jmb.2006.02.043
更新日期:2006-05-05 00:00:00
abstract::The biogenesis of the bacterial flagellum and chemotaxis apparatus in both Escherichia coli and Caulobacter crescentus requires the ordered expression of over 40 genes whose expression is controlled by a trans-acting regulatory hierarchy. In C. crescentus, additional control mechanisms ensure that the transcription of...
journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1016/0022-2836(89)90365-3
更新日期:1989-01-05 00:00:00
abstract::Although it has been known for many years that antibodies display properties characteristic of allosteric effectors, the molecular mechanisms responsible for these effects remain poorly understood. Here, we describe a single-domain antibody fragment (nanobody) that modulates protein function by constraining conformati...
journal_title:Journal of molecular biology
pub_type: 杂志文章
doi:10.1016/j.jmb.2011.01.017
更新日期:2011-03-18 00:00:00