Peroxidase catalysed cross-linking of an intrinsically unstructured protein via dityrosine bonds in the oocyst wall of the apicomplexan parasite, Eimeria maxima
Research output: Contribution to journal › Journal article › Research › peer-review
Standard
Peroxidase catalysed cross-linking of an intrinsically unstructured protein via dityrosine bonds in the oocyst wall of the apicomplexan parasite, Eimeria maxima. / Mai, Kelly; Smith, Nicholas C; Feng, Zhi-Ping; Katrib, Marilyn; Slapeta, Jan; Slapetova, Iveta; Wallach, Michael G; Luxford, Catherine; Davies, Michael Jonathan; Zhang, Xuecheng; Norton, Raymond S; Belli, Sabina I.
In: International Journal for Parasitology (Online), Vol. 41, No. 11, 09.2011, p. 1157-64.Research output: Contribution to journal › Journal article › Research › peer-review
Harvard
APA
Vancouver
Author
Bibtex
}
RIS
TY - JOUR
T1 - Peroxidase catalysed cross-linking of an intrinsically unstructured protein via dityrosine bonds in the oocyst wall of the apicomplexan parasite, Eimeria maxima
AU - Mai, Kelly
AU - Smith, Nicholas C
AU - Feng, Zhi-Ping
AU - Katrib, Marilyn
AU - Slapeta, Jan
AU - Slapetova, Iveta
AU - Wallach, Michael G
AU - Luxford, Catherine
AU - Davies, Michael Jonathan
AU - Zhang, Xuecheng
AU - Norton, Raymond S
AU - Belli, Sabina I
N1 - Copyright © 2011 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.
PY - 2011/9
Y1 - 2011/9
N2 - Apicomplexan parasites such as Eimeria maxima possess a resilient oocyst wall that protects them upon excretion in host faeces and in the outside world, allowing them to survive between hosts. The wall is formed from the contents of specialised organelles - wall-forming bodies - found in macrogametes of the parasites. The presence of dityrosine in the oocyst wall suggests that peroxidase-catalysed dityrosine cross-linking of tyrosine-rich proteins from wall-forming bodies forms a matrix that is a crucial component of oocyst walls. Bioinformatic analyses showed that one of these tyrosine-rich proteins, EmGAM56, is an intrinsically unstructured protein, dominated by random coil (52-70%), with some α-helix (28-43%) but a relatively low percentage of β-sheet (1-11%); this was confirmed by nuclear magnetic resonance and circular dichroism. Furthermore, the structural integrity of EmGAM56 under extreme temperatures and pH indicated its disordered nature. The intrinsic lack of structure in EmGAM56 could facilitate its incorporation into the oocyst wall in two ways: first, intrinsically unstructured proteins are highly susceptible to proteolysis, explaining the several differently-sized oocyst wall proteins derived from EmGAM56; and, second, its flexibility could facilitate cross-linking between these tyrosine-rich derivatives. An in vitro cross-linking assay was developed using a recombinant 42kDa truncation of EmGAM56. Peroxides, in combination with plant or fungal peroxidases, catalysed the rapid formation of dityrosine cross-linked polymers of the truncated EmGAM56, as determined by western blotting and HPLC, confirming this protein's propensity to form dityrosine bonds.
AB - Apicomplexan parasites such as Eimeria maxima possess a resilient oocyst wall that protects them upon excretion in host faeces and in the outside world, allowing them to survive between hosts. The wall is formed from the contents of specialised organelles - wall-forming bodies - found in macrogametes of the parasites. The presence of dityrosine in the oocyst wall suggests that peroxidase-catalysed dityrosine cross-linking of tyrosine-rich proteins from wall-forming bodies forms a matrix that is a crucial component of oocyst walls. Bioinformatic analyses showed that one of these tyrosine-rich proteins, EmGAM56, is an intrinsically unstructured protein, dominated by random coil (52-70%), with some α-helix (28-43%) but a relatively low percentage of β-sheet (1-11%); this was confirmed by nuclear magnetic resonance and circular dichroism. Furthermore, the structural integrity of EmGAM56 under extreme temperatures and pH indicated its disordered nature. The intrinsic lack of structure in EmGAM56 could facilitate its incorporation into the oocyst wall in two ways: first, intrinsically unstructured proteins are highly susceptible to proteolysis, explaining the several differently-sized oocyst wall proteins derived from EmGAM56; and, second, its flexibility could facilitate cross-linking between these tyrosine-rich derivatives. An in vitro cross-linking assay was developed using a recombinant 42kDa truncation of EmGAM56. Peroxides, in combination with plant or fungal peroxidases, catalysed the rapid formation of dityrosine cross-linked polymers of the truncated EmGAM56, as determined by western blotting and HPLC, confirming this protein's propensity to form dityrosine bonds.
KW - Biocatalysis
KW - Cell Wall
KW - Cross-Linking Reagents
KW - Eimeria
KW - Oocysts
KW - Peroxidase
KW - Protein Structure, Tertiary
KW - Protozoan Proteins
KW - Tyrosine
U2 - 10.1016/j.ijpara.2011.07.001
DO - 10.1016/j.ijpara.2011.07.001
M3 - Journal article
C2 - 21819990
VL - 41
SP - 1157
EP - 1164
JO - International Journal for Parasitology
JF - International Journal for Parasitology
SN - 0020-7519
IS - 11
ER -
ID: 129669627