Antiprotozoal glutathione derivatives with flagellar membrane binding activity against T. brucei rhodesiense

Perforin-like proteins (PLPs) play key roles in the mechanisms associated with parasitic disease caused by apicomplexans such as Plasmodium (malaria) and Toxoplasma. The T. gondii PLP1 (TgPLP1) mediates tachyzoite egress from cells, while the five Plasmodium PLPs carry out various roles in the life cycle of the parasite and with respect to the molecular basis of disease. Here we focus on Plasmodium vivax PLP1 and PLP2 (PvPLP1 and PvPLP2) compared to TgPLP1; PvPLP1 is important for invasion of mammalian hosts by the parasite and establishment of a chronic infection, PvPLP2 is important during the symptomatic blood stage of the parasite life cycle. Determination of the crystal structure of the membrane-binding APCβ domain of PvPLP1 reveals notable differences with that of TgPLP1, which are reflected in its inability to bind lipid bilayers in the way that TgPLP1 and PvPLP2 can be shown to. Molecular dynamics simulations combined with site-directed mutagenesis and functional assays allow a dissection of the binding interactions of TgPLP1 and PvPLP2 on lipid bilayers, and reveal a similar tropism for lipids found enriched in the inner leaflet of the mammalian plasma membrane. In addition to this shared mode of membrane binding PvPLP2 displays a secondary synergistic interaction side-on from its principal bilayer interface. This study underlines the substantial differences between the biophysical properties of the APCβ domains of Apicomplexan PLPs, which reflect their significant sequence diversity. Such differences will be important factors in determining the cell targeting and membrane-binding activity of the different proteins, in their different developmental roles within parasite life cycles.

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A dynamic loop provides dual control over the catalytic and membrane binding activity of a bacterial serine hydrolase

Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics ◽

10.1016/j.bbapap.2018.05.012 ◽

2018 ◽

Vol 1866 (9) ◽

pp. 925-932 ◽

Cited By ~ 1

Author(s):

Mackenzie A. Smith ◽

Whitney K. Phillips ◽

Perry L. Rabin ◽

R. Jeremy Johnson

Keyword(s):

Membrane Binding ◽

Binding Activity ◽

Dual Control ◽

Serine Hydrolase

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F-actin binds to the cytoplasmic surface of ponticulin, a 17-kD integral glycoprotein from Dictyostelium discoideum plasma membranes.

The Journal of Cell Biology ◽

10.1083/jcb.105.4.1741 ◽

1987 ◽

Vol 105 (4) ◽

pp. 1741-1751 ◽

Cited By ~ 63

Author(s):

L J Wuestehube ◽

E J Luna

Keyword(s):

Plasma Membrane ◽

Binding Site ◽

Dictyostelium Discoideum ◽

Plasma Membranes ◽

Membrane Binding ◽

Binding Activity ◽

Actin Binding ◽

Actin Binding Protein ◽

Cytoplasmic Surface ◽

Actin Binding Site

F-actin affinity chromatography and immunological techniques are used to identify actin-binding proteins in purified Dictyostelium discoideum plasma membranes. A 17-kD integral glycoprotein (gp17) consistently elutes from F-actin columns as the major actin-binding protein under a variety of experimental conditions. The actin-binding activity of gp17 is identical to that of intact plasma membranes: it resists extraction with 0.1 N NaOH, 1 mM dithiothreitol (DTT); it is sensitive to ionic conditions; it is stable over a wide range of pH; and it is eliminated by proteolysis, denaturation with heat, or treatment with DTT and N-ethylmaleimide. gp17 may be responsible for much of the actin-binding activity of plasma membranes since monovalent antibody fragments (Fab) directed primarily against gp17 inhibit actin-membrane binding by 96% in sedimentation assays. In contrast, Fab directed against cell surface determinants inhibit binding by only 0-10%. The actin-binding site of gp17 appears to be located on the cytoplasmic surface of the membrane since Fab against this protein continue to inhibit 96% of actin-membrane binding even after extensive adsorption against cell surfaces. gp17 is abundant in the plasma membrane, constituting 0.4-1.0% of the total membrane protein. A transmembrane orientation of gp17 is suggested since, in addition to the cytoplasmic localization of the actin-binding site, extracellular determinants of gp17 are identified. gp17 is surface-labeled by sulfo-N-hydroxy-succinimido-biotin, a reagent that cannot penetrate the cell membrane. Also, gp17 is glycosylated since it is specifically bound by the lectin, concanavalin A. We propose that gp17 is a major actin-binding protein that is important for connecting the plasma membrane to the underlying microfilament network. Therefore, we have named this protein "ponticulin" from the Latin word, ponticulus, which means small bridge.

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Membrane binding by CHMP7 coordinates ESCRT-III dependent nuclear envelope reformation

10.1101/049221 ◽

2016 ◽

Cited By ~ 1

Author(s):

Yolanda Olmos ◽

Anna Perdrix ◽

Jeremy G Carlton

Keyword(s):

Nuclear Envelope ◽

Membrane Binding ◽

Point Mutations ◽

Binding Activity ◽

Mitotic Exit ◽

Exit Point ◽

Cellular Functions ◽

Endosomal Sorting ◽

N Terminus ◽

And Function

AbstractAmongst other cellular functions, the Endosomal Sorting Complex Required for Transport-III (ESCRT-III) machinery controls nuclear envelope (NE) reformation during mitotic exit by sealing holes in the reforming NE. ESCRT-III also acts to repair this organelle upon migration-induced rupture. The ESCRT-III component CHMP7 is responsible for recruitment of ESCRT-III to the NE. Here, we show that the N-terminus of CHMP7, comprising tandem Winged Helix (WH)-domains, is a membrane-binding module. This activity allows CHMP7 to bind to the Endoplasmic Reticulum (ER), an organelle continuous with the NE, and provides a platform to direct NE-recruitment of ESCRT-III during mitotic exit. Point mutations that disrupt membrane-binding prevent CHMP7 localising to the ER and its subsequent enrichment at the reforming NE. These mutations prevent both assembly of downstream ESCRT-III components at the reforming NE and proper establishment of post-mitotic nucleo-cytoplasmic compartmentalisation. These data identify a novel membrane-binding activity within an ESCRT-III subunit that is essential for post-mitotic nuclear regeneration.One Sentence SummaryCHMP7’s atypical N-terminus is a membrane-binding module that allows assembly and function of ESCRT-III at the nuclear envelope during mitotic exit.

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Structural Basis for the Distinct Membrane Binding Activity of the Homologous C2A Domains of Myoferlin and Dysferlin

Journal of Molecular Biology ◽

10.1016/j.jmb.2019.04.006 ◽

2019 ◽

Vol 431 (11) ◽

pp. 2112-2126 ◽

Cited By ~ 5

Author(s):

Faraz M. Harsini ◽

Anthony A. Bui ◽

Anne M. Rice ◽

Sukanya Chebrolu ◽

Kerry L. Fuson ◽

...

Keyword(s):

Membrane Binding ◽

Binding Activity ◽

Structural Basis ◽

Distinct Membrane

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Influence of Acyl Chain Saturation on the Membrane-Binding Activity of a Short Antimicrobial Peptide

ACS Omega ◽

10.1021/acsomega.7b01270 ◽

2017 ◽

Vol 2 (11) ◽

pp. 7482-7492 ◽

Cited By ~ 11

Author(s):

Daniela Ciumac ◽

Richard A. Campbell ◽

Luke A. Clifton ◽

Hai Xu ◽

Giovanna Fragneto ◽

...

Keyword(s):

Antimicrobial Peptide ◽

Acyl Chain ◽

Membrane Binding ◽

Binding Activity

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CTP regulates membrane-binding activity of the nucleoid occlusion protein Noc

10.1101/2021.02.11.430593 ◽

2021 ◽

Author(s):

Adam S. B. Jalal ◽

Ngat T. Tran ◽

Ling J. Wu ◽

Karunakaran Ramakrishnan ◽

Martin Rejzek ◽

...

Keyword(s):

Membrane Binding ◽

Molecular Switches ◽

Binding Activity ◽

Biological Processes ◽

Control Functions ◽

Wide Range ◽

Nucleoprotein Complex ◽

Nucleoprotein Complexes ◽

Bacterial Cell Membrane

ABSTRACTATP and GTP-dependent molecular switches are extensively used to control functions of proteins in a wide range of biological processes. However, CTP switches are rarely reported. Here, we report a nucleoid occlusion protein Noc as the first example of a CTPase enzyme whose membrane-binding activity is directly regulated by a CTP switch. In Bacillus subtilis, Noc nucleates on 16-bp NBS sites before associating with neighboring non-specific DNA to form large membrane-associated nucleoprotein complexes to physically occlude assembly of the cell division machinery. By in vitro reconstitution, we show that (i) CTP is required for Noc to form the NBS-dependent nucleoprotein complex, and (ii) CTP binding, but not hydrolysis, switches Noc to a membrane-active state. Overall, we suggest that CTP couples membrane-binding activity of Noc to nucleoprotein complex formation to ensure productive recruitment of DNA to the bacterial cell membrane for nucleoid occlusion activity.

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