Plasmodium falciparum SSB tetramer binds single-stranded DNA only in a fully wrapped mode

Edwin Antony; Alexander G. Kozlov; Binh Nguyen; Timothy M. Lohman

doi:10.1016/j.jmb.2012.04.022

Plasmodium falciparum SSB tetramer binds single-stranded DNA only in a fully wrapped mode

Edwin Antony, Alexander G. Kozlov, Binh Nguyen, Timothy M. Lohman

Research output: Contribution to journal › Article › peer-review

25 Scopus citations

Abstract

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 52-65nt/tetramer. Pf-SSB does not transition to the more cooperative (SSB) ₃₅ DNA binding mode observed for Ec-SSB. Consistent with this, Pf-SSB tetramers also do not display the dramatic intra-tetramer negative cooperativity for binding of a second (dT)₃₅ molecule that is evident in Ec-SSB. These findings highlight variations in the DNA binding properties of these two highly conserved homotetrameric SSB proteins, and these differences might be tailored to suit their specific functions in the cell.

Original language	English
Pages (from-to)	284-295
Number of pages	12
Journal	Journal of Molecular Biology
Volume	420
Issue number	4-5
DOIs	https://doi.org/10.1016/j.jmb.2012.04.022
State	Published - Jul 20 2012

Keywords

DNA repair
malaria
recombination
replication
structure

Access to Document

10.1016/j.jmb.2012.04.022

Cite this

@article{4b13dea172f34cc9b8b877baff008611,

title = "Plasmodium falciparum SSB tetramer binds single-stranded DNA only in a fully wrapped mode",

abstract = "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 52-65nt/tetramer. Pf-SSB does not transition to the more cooperative (SSB) 35 DNA binding mode observed for Ec-SSB. Consistent with this, Pf-SSB tetramers also do not display the dramatic intra-tetramer negative cooperativity for binding of a second (dT)35 molecule that is evident in Ec-SSB. These findings highlight variations in the DNA binding properties of these two highly conserved homotetrameric SSB proteins, and these differences might be tailored to suit their specific functions in the cell.",

keywords = "DNA repair, malaria, recombination, replication, structure",

author = "Edwin Antony and Kozlov, {Alexander G.} and Binh Nguyen and Lohman, {Timothy M.}",

note = "Funding Information: We thank Thang Ho for synthesis and purification of the oligodeoxynucleotides, Dr. Wandy Beatty for assistance with the electron microscopy experiments, and Dr. R. Galletto for help with the smFRET instrument and experiments and Dr. Taekjip Ha for providing advice and software for the smFRET analysis. This work was supported in part by grants from the National Institutes of Health ( GM30498 and GM45948 ) to T.M.L.",

year = "2012",

month = jul,

day = "20",

doi = "10.1016/j.jmb.2012.04.022",

language = "English",

volume = "420",

pages = "284--295",

journal = "Journal of Molecular Biology",

issn = "0022-2836",

number = "4-5",

}

TY - JOUR

T1 - Plasmodium falciparum SSB tetramer binds single-stranded DNA only in a fully wrapped mode

AU - Antony, Edwin

AU - Kozlov, Alexander G.

AU - Nguyen, Binh

AU - Lohman, Timothy M.

N1 - Funding Information: We thank Thang Ho for synthesis and purification of the oligodeoxynucleotides, Dr. Wandy Beatty for assistance with the electron microscopy experiments, and Dr. R. Galletto for help with the smFRET instrument and experiments and Dr. Taekjip Ha for providing advice and software for the smFRET analysis. This work was supported in part by grants from the National Institutes of Health ( GM30498 and GM45948 ) to T.M.L.

PY - 2012/7/20

Y1 - 2012/7/20

N2 - 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 52-65nt/tetramer. Pf-SSB does not transition to the more cooperative (SSB) 35 DNA binding mode observed for Ec-SSB. Consistent with this, Pf-SSB tetramers also do not display the dramatic intra-tetramer negative cooperativity for binding of a second (dT)35 molecule that is evident in Ec-SSB. These findings highlight variations in the DNA binding properties of these two highly conserved homotetrameric SSB proteins, and these differences might be tailored to suit their specific functions in the cell.

AB - 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 52-65nt/tetramer. Pf-SSB does not transition to the more cooperative (SSB) 35 DNA binding mode observed for Ec-SSB. Consistent with this, Pf-SSB tetramers also do not display the dramatic intra-tetramer negative cooperativity for binding of a second (dT)35 molecule that is evident in Ec-SSB. These findings highlight variations in the DNA binding properties of these two highly conserved homotetrameric SSB proteins, and these differences might be tailored to suit their specific functions in the cell.

KW - DNA repair

KW - malaria

KW - recombination

KW - replication

KW - structure

UR - http://www.scopus.com/inward/record.url?scp=84862187368&partnerID=8YFLogxK

U2 - 10.1016/j.jmb.2012.04.022

DO - 10.1016/j.jmb.2012.04.022

M3 - Article

C2 - 22543238

AN - SCOPUS:84862187368

SN - 0022-2836

VL - 420

SP - 284

EP - 295

JO - Journal of Molecular Biology

JF - Journal of Molecular Biology

IS - 4-5

ER -

Plasmodium falciparum SSB tetramer binds single-stranded DNA only in a fully wrapped mode

Abstract

Keywords

Access to Document

Other files and links

Fingerprint

Cite this