Abstract:
:Hybrid genes were constructed to express bifunctional hybrid proteins in which staphyloccal nuclease A with or without an amino-terminal OmpA signal sequence was fused with TEM beta-lactamase (at the carboxyl terminal side) using the signal peptide of the major outer membrane lipoprotein of Escherichia coli as an internal linker. The hybrid proteins were found to be inserted in the membrane. Orientation of the hybrid protein with the OmpA signal peptide showed that the nuclease was translocated into the periplasm and the beta-lactamase remained in the cytoplasm. This indicates that the cleavable OmpA signal peptide served as a secretory signal for nuclease and the internal lipoprotein signal served as the transmembrane anchor. In the absence of the OmpA signal sequence the topology of the hybrid protein was reversed indicating that the internal lipoprotein signal peptide initially served as the signal peptide for the secretion of the carboxy terminal beta-lactamase domain across the membrane and subsequently as a membrane anchoring signal. The role of charged amino acids in the translocation and transmembrane orientation of membrane proteins was also analysed by introducing charged amino acids to either or both sides of the internal lipoprotein signal sequence in the bifunctional hybrid proteins in the absence of the amino-terminal signal sequence. Introduction of two lysine residues at the carboxy-terminal side of the internal signal sequence reversed the topology of the transmembrane protein by translocating the amino-terminal nuclease domain across the membrane, leaving the carboxyl terminal beta-lactamase domain in the cytoplasm. When three more lysine residues were added to the amino-terminal side of the internal signal sequence of the same construct the membrane topology flipped back to the original orientation. A similar reversion of the topology could be obtained by introducing negatively charged residues at the amino-terminal side of the internal signal sequence. Present results demonstrate for the first time that a bifunctional transmembrane protein can be engineered to assume either of the two opposite orientations and that charge balance around the transmembrane domain is a major factor in controlling the topology of a transmembrane protein.
journal_name
Mol Microbioljournal_title
Molecular microbiologyauthors
Kim H,Paul S,Gennity J,Jennity J corrected to Gennity J,Inouye Mdoi
10.1111/j.1365-2958.1994.tb00360.xsubject
Has Abstractpub_date
1994-03-01 00:00:00pages
819-31issue
5eissn
0950-382Xissn
1365-2958journal_volume
11pub_type
杂志文章abstract::We have followed the time-dependent transfection of Paramecium cells with a vector containing the gene of green fluorescent protein (GFP) attached to the C-terminus of the PtSERCA1 gene. The outlines of alveolar sacs (ASs) are labelled, as is the endoplasmic reticulum (ER) throughout the cell. When GFP fluorescence is...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2000.02038.x
更新日期:2000-08-01 00:00:00
abstract::A hallmark of the biofilm architecture is the presence of microcolonies. However, little is known about the underlying mechanisms governing microcolony formation. In the pathogen Pseudomonas aeruginosa, microcolony formation is dependent on the two-component regulator MifR, with mifR mutant biofilms exhibiting an over...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.12018
更新日期:2012-11-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.12890
更新日期:2015-02-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章,评审
doi:10.1046/j.1365-2958.1998.01049.x
更新日期:1998-10-01 00:00:00
abstract::Biofilm formation is a social behaviour that generates favourable conditions for sustained survival in the natural environment. For the Gram-positive bacterium Bacillus subtilis the process involves the differentiation of cell fate within an isogenic population and the production of communal goods that form the biofil...
journal_title:Molecular microbiology
pub_type: 杂志文章,评审
doi:10.1111/mmi.12697
更新日期:2014-08-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1996.00133.x
更新日期:1996-11-01 00:00:00
abstract::The recently identified recA gene of the naturally transformable bacterium Streptococcus pneumoniae has been further characterized by constructing a recA null mutation and by investigating its regulation. The recA mutation has been shown to confer both DNA repair (as judged from sensitivity to u.v. and methyl methane ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1995.tb02250.x
更新日期:1995-01-01 00:00:00
abstract::The presence of very different sets of enzymes, and in particular the presence of RNase E and RNase J, has been used to explain significant differences in RNA metabolism between the two model organisms Escherichia coli and Bacillus subtilis. However, these studies might have somewhat polarized our view of RNA metaboli...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2011.07888.x
更新日期:2011-12-01 00:00:00
abstract::The NAC (nitrogen assimilation control) protein from Klebsiella aerogenes is a LysR-like regulator for transcription of several operons involved in nitrogen metabolism, and couples the transcription of these sigma 70-dependent operons to regulation by the sigma 54-dependent NTR system. NAC activates expression of oper...
journal_title:Molecular microbiology
pub_type: 杂志文章,评审
doi:10.1111/j.1365-2958.1991.tb01965.x
更新日期:1991-11-01 00:00:00
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pub_type: 杂志文章
doi:10.1046/j.1365-2958.1999.01382.x
更新日期:1999-05-01 00:00:00
abstract::Previous evidence showed that b- and a-type flagellins of Pseudomonas aeruginosa are modified in vivo by phosphorylation at tyrosine. This research was designed to demonstrate phosphorylation of flagellin at tyrosine in vitro. Evidence presented showed that flagellin is labelled by [gamma-32P]-ATP, but not by [alpha-3...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1994.tb01078.x
更新日期:1994-06-01 00:00:00
abstract::Plasmodium falciparum erythrocyte membrane protein-1 (PfEMP-1) is exposed on the surface of infected erythrocytes where it both acts as an important pathogenicity factor in malaria and undergoes antigenic variation as a means of immune evasion. Because the mammalian erythrocyte lacks a protein secretory machinery ther...
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pub_type: 杂志文章
doi:10.1111/j.1365-2958.2004.04468.x
更新日期:2005-02-01 00:00:00
abstract::Calcineurin plays essential roles in virulence and growth of pathogenic fungi and is a target of the natural products FK506 and Cyclosporine A. In the pathogenic mucoralean fungus Mucor circinelloides, calcineurin mutation or inhibition confers a yeast-locked phenotype indicating that calcineurin governs the dimorphic...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.13071
更新日期:2015-09-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2001.02553.x
更新日期:2001-08-01 00:00:00
abstract::Various physiological stimuli trigger the conversion of noninfective Leishmania donovani promastigotes to the infective form. Here, we present the first evidence of the effect of glucose starvation, on virulence and survival of these parasites. Glucose starvation resulted in a decrease in metabolically active parasite...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.13534
更新日期:2016-12-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.12743
更新日期:2014-10-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1999.01593.x
更新日期:1999-10-01 00:00:00
abstract::Linear plasmids and chromosomes of Streptomyces carry terminal proteins (TPs) covalently attached to the 5' ends of the DNA. Most known telomeres are conserved in primary sequence and in the potential secondary structures formed during replication. The TP that caps these telomeres is also highly conserved and its codi...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2007.05616.x
更新日期:2007-03-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
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更新日期:2012-05-01 00:00:00
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pub_type: 杂志文章
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更新日期:2015-01-01 00:00:00
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pub_type: 杂志文章
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pub_type: 杂志文章
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更新日期:2001-04-01 00:00:00
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pub_type: 杂志文章
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更新日期:2009-10-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1994.tb00298.x
更新日期:1994-01-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1992.tb01757.x
更新日期:1992-10-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.14593
更新日期:2020-12-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
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更新日期:1996-03-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1996.5201047.x
更新日期:1996-05-01 00:00:00
abstract::In the yeast Saccharomyces cerevisiae, PKA and Sch9 exert similar physiological roles in response to nutrient availability. However, their functional redundancy complicates to distinguish properly the target genes for both kinases. In this article, we analysed different phenotypic read-outs. The data unequivocally sho...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2004.04429.x
更新日期:2005-02-01 00:00:00
abstract::CoiA is a transient protein expressed specifically during competence and required for genetic transformation in Streptococcus pneumoniae, but not for DNA uptake. It is widely conserved among Gram-positive bacteria but its function is unknown. Here we report that although the rate of DNA uptake was not affected in a co...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2006.05558.x
更新日期:2007-02-01 00:00:00