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Full-Text Articles in Life Sciences
Rad51 Nucleoprotein Filament Disassembly Captured Using Fluorescent Plasmodium Falciparum Ssb As A Reporter For Single-Stranded Dna, Eric Parker Davenport, Derek F. Harris, Sofia Origanti, Edwin Antony
Rad51 Nucleoprotein Filament Disassembly Captured Using Fluorescent Plasmodium Falciparum Ssb As A Reporter For Single-Stranded Dna, Eric Parker Davenport, Derek F. Harris, Sofia Origanti, Edwin Antony
Biological Sciences Faculty Research and Publications
Single-stranded DNA binding (SSB) proteins coordinate DNA replication, repair, and recombination and are critical for maintaining genomic integrity. SSB binds to single-stranded DNA (ssDNA) rapidly and with very high affinity making it a useful molecular tool to detect free ssDNA in solution. We have labeled SSB from Plasmodium falciparum (Pf-SSB) with the MDCC (7-diethylamino-3-((((2-maleimidyl)ethyl)amino)-carbonyl)coumarin) fluorophore which yields a four-fold increase in fluorescence upon binding to ssDNA. Pf-SSBMDCC binding to DNA is unaffected by NaCl or Mg2+ concentration and does not display salt-dependent changes in DNA binding modes or cooperative binding on long DNA substrates. These …
Intrinsically Disordered C-Terminal Tails Of E. Coli Single-Stranded Dna Binding Protein Regulate Cooperative Binding To Single-Stranded Dna, Alexander G. Kozlov, Elizabeth A. Weiland, Anuradha Mittal, Vince Waldman, Edwin Antony, Nicole Fazio, Rohit V. Pappu, Timothy M. Lohman
Intrinsically Disordered C-Terminal Tails Of E. Coli Single-Stranded Dna Binding Protein Regulate Cooperative Binding To Single-Stranded Dna, Alexander G. Kozlov, Elizabeth A. Weiland, Anuradha Mittal, Vince Waldman, Edwin Antony, Nicole Fazio, Rohit V. Pappu, Timothy M. Lohman
Biological Sciences Faculty Research and Publications
The homotetrameric Escherichia coli single-stranded DNA binding protein (SSB) plays a central role in DNA replication, repair and recombination. E. coli SSB can bind to long single-stranded DNA (ssDNA) in multiple binding modes using all four subunits [(SSB)65 mode] or only two subunits [(SSB)35 binding mode], with the binding mode preference regulated by salt concentration and SSB binding density. These binding modes display very different ssDNA binding properties with the (SSB)35 mode displaying highly cooperative binding to ssDNA. SSB tetramers also bind an array of partner proteins, recruiting them to their sites of action. This is …
Multiple C-Terminal Tails Within A Single E. Coli Ssb Homotetramer Coordinate Dna Replication And Repair, Edwin Antony, Elizabeth Weiland, Quan Yuan, Carol M. Manhart, Binh Nguyen, Alexander G. Kozlov, Charles S. Mchenry, Timothy M. Lohman
Multiple C-Terminal Tails Within A Single E. Coli Ssb Homotetramer Coordinate Dna Replication And Repair, Edwin Antony, Elizabeth Weiland, Quan Yuan, Carol M. Manhart, Binh Nguyen, Alexander G. Kozlov, Charles S. Mchenry, Timothy M. Lohman
Biological Sciences Faculty Research and Publications
Escherichia coli single-stranded DNA binding protein (SSB) plays essential roles in DNA replication, recombination and repair. SSB functions as a homotetramer with each subunit possessing a DNA binding domain (OB-fold) and an intrinsically disordered C-terminus, of which the last nine amino acids provide the site for interaction with at least a dozen other proteins that function in DNA metabolism. To examine how many C-termini are needed for SSB function, we engineered covalently linked forms of SSB that possess only one or two C-termini within a four-OB-fold “tetramer”. Whereas E. coli expressing SSB with only two tails can survive, expression …
Plasmodium Falciparum Ssb Tetramer Binds Single-Stranded Dna Only In A Fully Wrapped Mode, Edwin Antony, Alexander G. Kozlov, Binh Nguyen, Timothy M. Lohman
Plasmodium Falciparum Ssb Tetramer Binds Single-Stranded Dna Only In A Fully Wrapped Mode, Edwin Antony, Alexander G. Kozlov, Binh Nguyen, Timothy M. Lohman
Biological Sciences Faculty Research and Publications
The tetrameric Escherichia coli single-stranded DNA (ssDNA) binding protein (Ec-SSB) functions in DNA metabolism by binding to ssDNA and interacting directly with numerous DNA repair and replication proteins. Ec-SSB tetramers can bind ssDNA in multiple DNA binding modes that differ in the extent of ssDNA wrapping. Here, we show that the structurally similar SSB protein from the malarial parasite Plasmodium falciparum (Pf-SSB) also binds tightly to ssDNA but does not display the same number of ssDNA binding modes as Ec-SSB, binding ssDNA exclusively in fully wrapped complexes with site sizes of 52–65 nt/tetramer. Pf …
Plasmodium Falciparum Ssb Tetramer Wraps Single-Stranded Dna With Similar Topology But Opposite Polarity To E. Coli Ssb, Edwin Antony, Elizabeth A. Weiland, Sergey Korolev, Timothy M. Lohman
Plasmodium Falciparum Ssb Tetramer Wraps Single-Stranded Dna With Similar Topology But Opposite Polarity To E. Coli Ssb, Edwin Antony, Elizabeth A. Weiland, Sergey Korolev, Timothy M. Lohman
Biological Sciences Faculty Research and Publications
Single-stranded DNA binding (SSB) proteins play central roles in genome maintenance in all organisms. Plasmodium falciparum, the causative agent of malaria, encodes an SSB protein that localizes to the apicoplast and likely functions in the replication and maintenance of its genome. P. falciparum SSB (Pf-SSB) shares a high degree of sequence homology with bacterial SSB proteins but differs in the composition of its C-terminus, which interacts with more than a dozen other proteins in Escherichia coli SSB (Ec-SSB). Using sedimentation methods, we show that Pf-SSB forms a stable homo-tetramer alone and when bound to …