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Sophie Debs Amy Cohen Elham Hosseini-Beheshti Giovanna Chimini Nicholas H. Hunt Georges E.R. Grau 《Biochimica et Biophysica Acta (BBA)/General Subjects》2019,1863(2):325-331
Background
Malaria is a serious parasitic infection affecting millions of people worldwide each year. Cerebral malaria is the most severe complication of Plasmodium infections, predominantly affecting children. Extracellular vesicles are essential mediators of intercellular communication and include apoptotic bodies, microvesicles and exosomes. Microvesicle numbers increase during disease pathogenesis and inhibition of their release can prevent brain pathology and mortality.Scope of review
We explore the current knowledge on microvesicles and exosomes in cerebral malaria pathogenesis.Major conclusions
Microvesicles and exosomes are implicated in cerebral malaria pathogenesis, in the modulation of host immunity to Plasmodium, and in cell-cell communication. Blocking their production is protective in models of cerebral malaria, both in vivo and in vitro.General significance
While anti-malarial treatments exist to combat Plasmodium infections, increasing drug resistance presents a major challenge. In order to improve diagnosis and treatment outcomes, further research is required to better appreciate extracellular vesicle involvement in cerebral malaria. 相似文献3.
Tae Sup Lee Young Kim Weiqi Zhang In Ho Song Ching-Hsuan Tung 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(5):1091-1100
Background
Exosomes are nano-sized vesicles derived from the fusion of multivesicular bodies with the surrounding plasma membrane. Exosomes have various diagnostic and therapeutic potentials in cancer and other diseases, thus tracking exosomes is an important issue.Methods
Here, we report a facile exosome labeling strategy using a natural metabolic incorporation of an azido-sugar into the glycan, and a strain-promoted azide-alkyne click reaction. In culture, tetra-acetylated N-azidoacetyl-D-mannosamine (Ac4ManNAz) was spontaneously incorporated into glycans within the cells and later redistributed onto their exosomes. These azido-containing exosomes were then labeled with azadibenzylcyclooctyne (ADIBO)-fluorescent dyes by a bioorthogonal click reaction.Results
Cellular uptake and the in vivo tracking of fluorescent labeled exosomes were evaluated in various cells and tumor bearing mice. Highly metastatic cancer-derived exosomes showed an increased self-homing in vitro and selective organ distribution in vivo.Conclusion
Our metabolic exosome labeling strategy could be a promising tool in studying the biology and distribution of exosomes, and optimizing exosome based therapeutic approaches.General significant
A facile and effective exosome labeling strategy was introduced by presenting azido moiety on the surface of exosome through metabolic glycan synthesis, and then conjugating a strain-promoted fluorescent dye. 相似文献4.
Sumangala Shetty Paul R. Copeland 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(11):2506-2510
Background
Selenoprotein synthesis requires the reinterpretation of a UGA stop codon as one that encodes selenocysteine (Sec), a process that requires a set of dedicated translation factors. Among the mammalian selenoproteins, Selenoprotein P (SELENOP) is unique as it contains a selenocysteine-rich domain that requires multiple Sec incorporation events.Scope of review
In this review we elaborate on new data and current models that provide insight into how SELENOP is made.Major conclusions
SELENOP synthesis requires a specific set of factors and conditions.General significance
As the key protein required for proper selenium distribution, SELENOP stands out as a lynchpin selenoprotein that is essential for male fertility, proper neurologic function and selenium metabolism. 相似文献5.
Guillem Prats-Ejarque Jose A. Blanco Vivian A. Salazar Victòria M. Nogués Mohammed Moussaoui Ester Boix 《Biochimica et Biophysica Acta (BBA)/General Subjects》2019,1863(1):105-117
Background
Human RNase6 is a small cationic antimicrobial protein that belongs to the vertebrate RNaseA superfamily. All members share a common catalytic mechanism, which involves a conserved catalytic triad, constituted by two histidines and a lysine (His15/His122/Lys38 in RNase6 corresponding to His12/His119/Lys41 in RNaseA). Recently, our first crystal structure of human RNase6 identified an additional His pair (His36/His39) and suggested the presence of a secondary active site.Methods
In this work we have explored RNase6 and RNaseA subsite architecture by X-ray crystallography, site-directed mutagenesis and kinetic characterization.Results
The analysis of two novel crystal structures of RNase6 in complex with phosphate anions at atomic resolution locates a total of nine binding sites and reveals the contribution of Lys87 to phosphate-binding at the secondary active center. Contribution of the second catalytic triad residues to the enzyme activity is confirmed by mutagenesis. RNase6 catalytic site architecture has been compared with an RNaseA engineered variant where a phosphate-binding subsite is converted into a secondary catalytic center (RNaseA-K7H/R10H).Conclusions
We have identified the residues that participate in RNase6 second catalytic triad (His36/His39/Lys87) and secondary phosphate-binding sites. To note, residues His39 and Lys87 are unique within higher primates. The RNaseA/RNase6 side-by-side comparison correlates the presence of a dual active site in RNase6 with a favored endonuclease-type cleavage pattern.General significance
An RNase dual catalytic and extended binding site arrangement facilitates the cleavage of polymeric substrates. This is the first report of the presence of two catalytic centers in a single monomer within the RNaseA superfamily. 相似文献6.
Philippe Marchetti Anne Trinh Raeeka Khamari Jerome Kluza 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(4):999-1005
Background
Besides its influence on survival, growth, proliferation, invasion and metastasis, cancer cell metabolism also greatly influences the cellular responses to molecular-targeted therapies.Scope of the review
To review the recent advances in elucidating the metabolic effects of BRAF and MEK inhibitors (clinical inhibitors of the MAPK/ERK pathway) in melanoma and discuss the underlying mechanisms involved in the way metabolism can influence melanoma cell death and resistance to BRAF and MEK inhibitors. We also underlined the therapeutic perspectives in terms of innovative drug combinations.Major conclusion
BRAF and MEK inhibitors inhibit aerobic glycolysis and induce high levels of metabolic stress leading to effective cell death by apoptosis in BRAF-mutated cancer cells. An increase in mitochondrial metabolism is required to survive to MAPK/ERK pathway inhibitors and the sub-population of cells that survives to these inhibitors are characterized by mitochondrial OXPHOS phenotype. Consequently, mitochondrial inhibition could be combined with oncogenic “drivers” inhibitors of the MAPK/ERK pathway for improving the efficacy of molecular-targeted therapy.General significance
Metabolism is a key component of the melanoma response to BRAF and/or MEK inhibitors. Mitochondrial targeting may offer novel therapeutic approaches to overwhelm the mitochondrial addiction that limits the efficacy of BRAF and/or MEK inhibitors. These therapeutic approaches might be quickly applicable to the clinical situation. 相似文献7.
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Shruti Chakraborty Sayak Ganguli Aritra Chowdhury Michael Ibba Rajat Banerjee 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(8):1801-1809
Background
Under oxidative stress cytoplasmic aminoacyl-tRNA synthetase (aaRSs) substrate specificity can be compromised, leading to tRNA mischarging and mistranslation of the proteome. Whether similar processes occur in mitochondria, which are major cellular sources of reactive oxygen species (ROS), is unknown. However, relaxed substrate specificity in yeast mitochondrial phenylalanyl-tRNA synthetase (ScmitPheRS) has been reported to increase tRNA mischarging and blocks mitochondrial biogenesis.Methods
Non-reducing denaturing PAGE, cysteine reactivity studies, MALDI-TOF mass spectrometry, enzyme assay, western blot, growth assay, circular dichroism, dynamic light scattering and fluorescence spectroscopy were used to study the effect of oxidative stress on ScmitPheRS activity.Results
ScmitPheRS is reversibly inactivated under oxidative stress. The targets for oxidative inactivation are two conserved cysteine residues resulting in reversible intra-molecular disulfide bridge formation. Replacement of either conserved cysteine residue increased viability during growth under oxidative stress.Conclusion
Formation of intra-molecular disulfide bridge under oxidative stress hinders the tRNAPhe binding of the enzyme, thus inactivating ScmitPheRS reversibly.General significance
The ScmitPheRS activity is compromised under oxidative stress due to formation of intra-molecular disulfide bridge. The sensitivity of ScmitPheRS to oxidation may provide a protective mechanism against error-prone translation under oxidative stress. 相似文献9.
Joanna Strumillo Katarzyna E. Nowak Anita Krokosz Aleksandra Rodacka Mieczyslaw Puchala Grzegorz Bartosz 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(4):877-885
Background
Nitric oxide is a well-known gaseous signaling molecule and protein modifying agent. However, at higher concentrations or during oxidative stress nitric oxide may exert some deleterious effects on protein structure and function. Here we investigated the influence of nitric oxide and products of its oxidation on two glycolytic enzymes: GAPDH and LDH under in vitro nitrosative stress conditions. Secondly, we applied natural antioxidants: melatonin and resveratrol to examine their effects on the enzymes under studied conditions.Methods
By means of UV–VIS and fluorescence spectroscopy methods we compared nitric oxide mediated changes of enzyme activities, amount of free sulfhydryl groups (-SH) and bis-ANS probe binding. Finally, we predicted potential cysteine residues modified by nitric oxide in studied proteins using GPS-SNO software.Results
Our results indicated that nitric oxide reversibly inactivates GAPDH but does not affect the activity of LDH. Nitric oxide dependent GAPDH activity decline was accompanied by the reduction of the amount of free –SH groups and GAPDH-bound bis-ANS fluorescence. Reduction of the number of free –SH groups and protein-bound bis-ANS fluorescence was also observed in LDH treated with NO. Applied antioxidants increased inactivation of GAPDH and structural changes of GAPDH and LDH.Conclusions
Nitric oxide modifies function and structure of thiol-dependent enzyme such as GAPDH and structure of LDH which function do not rely on cysteine thiols. Both resveratrol and melatonin exerted prooxidative properties in studied conditions.General significance
Extensively studied antioxidants: resveratrol and melatonin may function as a prooxidative species under in vitro nitrosative stress conditions. 相似文献10.
Seong-Cheol Park Il Ryong Kim Jin-Young Kim Yongjae Lee Eun-Ji Kim Ji Hyun Jung Young Jun Jung Mi-Kyeong Jang Jung Ro Lee 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(12):2545-2554
Background
It remains an open question whether plant phloem sap proteins are functionally involved in plant defense mechanisms.Methods
The antifungal effects of two profilin proteins from Arabidopsis thaliana, AtPFN1 and AtPFN2, were tested against 11 molds and 4 yeast fungal strains. Fluorescence profiling, biophysical, and biochemical analyses were employed to investigate their antifungal mechanism.Results
Recombinant AtPFN1 and AtPFN2 proteins, expressed in Escherichia coli, inhibited the cell growth of various pathogenic fungal strains at concentrations ranging from 10 to 160?μg/mL. The proteins showed significant intracellular accumulation and cell-binding affinity for fungal cells. Interestingly, the AtPFN proteins could penetrate the fungal cell wall and membrane and act as inhibitors of fungal growth via generation of cellular reactive oxygen species and mitochondrial superoxide. This triggered the AtPFN variant-induced cell apoptosis, resulting in morphological changes in the cells.Conclusion
PFNs may play a critical role as antifungal proteins in the Arabidopsis defense system against fungal pathogen attacks.General significance
The present study indicates that two profilin proteins, AtPFN1 and AtPFN2, can act as natural antimicrobial agents in the plant defense system. 相似文献11.
Chaturaka Rodrigo Fabio Luciani 《Biochimica et Biophysica Acta (BBA)/General Subjects》2019,1863(2):511-519
Background
Next generation sequencing (NGS) methods have significantly contributed to a paradigm shift in genomic research for nearly a decade now. These methods have been useful in studying the dynamic interactions between RNA viruses and human hosts.Scope of the review
In this review, we summarise and discuss key applications of NGS in studying the host – pathogen interactions in RNA viral infections of humans with examples.Major conclusions
Use of NGS to study globally relevant RNA viral infections have revolutionized our understanding of the within host and between host evolution of these viruses. These methods have also been useful in clinical decision-making and in guiding biomedical research on vaccine design.General significance
NGS has been instrumental in viral genomic studies in resolving within-host viral genomic variants and the distribution of nucleotide polymorphisms along the full-length of viral genomes in a high throughput, cost effective manner. In the future, novel advances such as long read, single molecule sequencing of viral genomes and simultaneous sequencing of host and pathogens may become the standard of practice in research and clinical settings. This will also bring on new challenges in big data analysis. 相似文献12.
Najeh Krayem Goetz Parsiegla Hélène Gaussier Hanen Louati Raida Jallouli Pascal Mansuelle Frédéric Carrière Youssef Gargouri 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(5):1247-1261
Background
Heterodimeric phospholipase A2 from venom glands of Tunisian scorpion Scorpio maurus (Sm-PLGV) had been purified. It contains long and short chains linked by a disulfide bridge. Sm-PLGV exhibits hemolytic activity towards human erythrocytes and interacts with phospholipid monolayers at high surface pressure. The investigation of structure-function relationships should provide new clues to understand its activity.Methods
Molecular cloning of Sm-PLGV and heterologous expression in Escherichia coli of three recombinant forms was used to determine the role of the short chain on enzymatic activity. Infrared spectroscopy assisted 3D model building of the three recombinant constructs (phospholipases with and without the penta-peptide and Long chain only) allowed us to propose an explanation of the differences in specific activities and their interaction with various phospholipids.Results
Nucleotide sequence of Sm-PLGV encodes 129 residues corresponding to the Long chain, the penta-peptide and the short chain. Although recombinant phospholipases without and with the penta-peptide have different specific activities, they display a similar substrate specificity on various phospholipid monolayers and similar bell-shaped activity profiles with maxima at high surface pressure. The absence of the short chain reduces significantly enzymatic and hemolytic activities. The 3D models pointed to an interaction of the short chain with the catalytic residues, what might explain the difference in activities of our constructs.Conclusion
Infrared spectroscopy data and 3D modeling confirm the experimental findings that highlight the importance of the short chain for the Sm-PLGV activity.General significance
New informations are given to further establish the structure-function relationships of the Sm-PLGV. 相似文献13.
Christian Borgo Jordi Vilardell Valentina Bosello-Travain Lorenzo A. Pinna Andrea Venerando Mauro Salvi 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(12):2902-2910
Background
HSP27 plays a role in various diseases, including neurodegenerative diseases, ischemia, and atherosclerosis. It is particularly important in the regulation of the development, progression and metastasis of cancer as well as cell apoptosis and drug resistance. However, the absence of an ATP binding domain, that is, instead, present in other HSPs such as HSP90 and HSP70, hampers the development of small molecules as inhibitors of HSP27.Methods
Knockout cell lines generated by Crispr/Cas9 gene editing tool, specific kinase inhibitors and siRNA transfections were exploited to demonstrate that the expression of HSP27 is dependent on the integrity/activity of protein kinase CK2 holoenzyme. The interaction between these proteins has been confirmed by co-immunoprecipitation, confocal immunofluorescence microscopy, and by density gradient separation of protein complexes. Finally, using a proliferation assay this study demonstrates the potential efficacy of a combinatory therapy of heath shock and CK2 inhibitors in cancer treatment.Results
Our data demonstrate that CK2 is able to regulate HSP27 turnover by affecting the expression of its ubiquitin ligase SMURF2 (Smad ubiquitination regulatory factor 2). Moreover, for the first time we show an increased sensitivity of CK2-inhibited tumour cells to hyperthermia treatment.Conclusion
Being HSP27 involved in several pathological conditions, including protein conformational diseases (i.e Cystic Fibrosis) and cancer, the need of drugs to modulate its activity is growing and CK2-targeting could represent a new strategy to reduce cellular HSP27 level.General significance
This study identifies CK2 as a molecular target to control HSP27 cellular expression. 相似文献14.
Si-Eun Yun Min-Kyung Nam Hyangshuk Rhim 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(7):1602-1611
Background
Regulating apoptosis is a common and essential therapeutic strategy for cancer and neurodegenerative disorders. Based on basic studies of apoptotic mechanisms, various researches have attempted to overcome the pathogenesis of such diseases by activating or inhibiting apoptosis. Generally, the biochemical characteristics of the target molecules should be evaluated along with understanding of their mechanisms of action during drug development. Among apoptotic regulators, XIAP serves as a potent negative regulator to block apoptosis through the inhibition of caspase (CASP)-9 and -3/7. Although XIAP is an attractive target with such apoptotic-modulating property, biochemical and biophysical studies of XIAP are still challenging.Methods
In this study, the CASP-9 and -3/7 inhibitors XIAP, 242Δ and Δ230 were prepared using the pGEX expression system and biochemically characterized.Results
These inhibitors were expressed in Escherichia coli at a concentration of ≥20?mg/L culture under a native condition with 0.01?mM IPTG induction. Notably, using a simple and rapid affinity purification technique, these CASP-9 and -3/7 inhibitors have been purified, yielding ≥5?mg/L culture at approximately 90% purity.Conclusions
We have determined that HtrA2 specifically binds to the BIR2 and BIR3 of XIAP at a 1:1 molecular ratio. Moreover, in vitro cell-free CASP-9 and -3/7 activation-apoptosis assays have demonstrated that these purified XIAP proteins dramatically inhibit CASP-9 and -3/7 action.General significance
Our system is suitable for biochemical studies, such as quantitation of the number of molecules acting on the apoptosis regulation, and provides a basis and insights that can be applied to the development of therapeutic agents for neurodegenerative disorders and cancer. 相似文献15.
Huan He Juan Xu Wen Xie Qing-Lian Guo Feng-Lei Jiang Yi Liu 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(3):501-512
Background
CDK6 is considered as a highly validated anticancer drug target due to its essential role in regulating cell cycle progression at G1 restriction point. Activation of CDK6 requires the phosphorylation of Thr177 on A-loop, but the structural insights of the activation mechanism remain unclear.Methods
Herein, all-atoms molecular dynamics (MD) simulations were used to study the effects of Thr177 phosphorylation on the dynamic structure of CDK6-Vcyclin complex.Results
MD results indicated that the free energy barrier of the transition from open to closed state decreased ~ 47.2% after Thr177 phosphorylation. Key steps along the state transition process were obtained from a cluster analysis. Binding preference of ten different inhibitors to open or closed state were also investigated through molecular docking along with MD simulations methods.Conclusions
Our results indicated that Thr177 phosphorylation increased the flexibility around the ATP-binding pocket. The transition of the ATP-binding pocket between open and closed states should be considered for understanding the binding of CDK6 inhibitors.General significance
This work could deepen the understanding of CDKs activation mechanism, and provide useful information for the discovery of new CDKs inhibitors with high affinity and specificity. 相似文献16.
Meenakshi Sharma Dinesh Kumar Krishna Mohan Poluri 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(4):924-935
Background
Characterization of partially collapsed protein conformations at atomic level is a daunting task due to their inherent flexibility and conformational heterogeneity. T7 bacteriophage endolysin (T7L) is a single-domain amidase that facilitates the lysis of Gram-negative bacteria. T7L exhibits a pH-dependent structural transition from native state to partially folded (PF) conformation. In the pH range 5–3, T7L PF states display differential ANS binding characteristics.Methods
CD, fluorescence, NMR spectroscopy and lysis assays were used to investigate the structure-stability- dynamics relationships of T7L PF conformations.Results
Structural studies indicated a partial loss of secondary/tertiary structures compared to its native state. The loss in the tertiary structure and the hydrophobic core opening increases upon decrease of pH from 5 to 3. Thermal denaturation experiments delineated that the pH?5 conformation is thermally irreversible in contrast to pH?3, depicting that hydrophobic core opening is essential for thermal reversibility. Further, urea dependent unfolding features of PF state at pH?5 and 4 evidenced for a collapsed conformation at intermediate urea concentrations. Residue level studies revealed that α1-helix and β3-β4 segment of T7L are the major contributors for such a structural collapse and inherent dynamics.Conclusions
The results suggested that the low pH PF states of T7L are heterogeneous and exhibits differential structural, unfolding, thermal reversibility, and dynamic features.General significance
Unraveling the structure-stability characteristics of different endolysin conformations is essential for designing novel chimeric and engineered phage endolysins as broadband antimicrobial agents over a varied pH range. 相似文献17.
Lei Li Ryan Z.L. Lim Lawrence S.U. Lee Nicholas S.Y. Chew 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(8):1790-1800
Background
HIV infection and/or the direct pathogenic effects of circulating HIV proteins impairs the physiological function of mesenchymal stem cells (MSCs), and contribute to the pathogenesis of age-related clinical comorbidities in people living with HIV. The SDF-1/CXCR4 pathway is vital for modulating MSC proliferation, migration and differentiation. HIV glycoprotein gp120 inhibits SDF-1 induced chemotaxis by downregulating the expression and function of CXCR4 in monocytes, B and T cells. The influence of gp120 on CXCR4 expression and migration in MSCs is unknown.Methods
We investigated CXCR4 expression and SDF-1/CXCR4-mediated MSC migration in response to gp120, and its effect on downstream signaling pathways: focal adhesion kinase (FAK)/Paxillin and extracellular signal-regulated kinase (ERK).Results
Gp120 upregulated MSC CXCR4 expression. This potentiated the effects of SDF-1 in inducing chemotaxis; FAK/Paxillin and ERK pathways were over-activated, thereby facilitating actin stress fiber reorganization. CXCR4 blockage or depletion abrogated the observed effects.Conclusion
Gp120 from both T- and M- tropic HIV strains upregulated CXCR4 expression in MSCs, resulting in enhanced MSC chemotaxis in response to SDF-1.General significance
HIV infection and its proteins are known to disrupt physiological differentiation of MSC; increased gp120-driven migration amplifies the total MSC population destined for ineffective and inappropriate differentiation, thus contributing to the pathogenesis of HIV-related comorbidities. Additionally, given that MSCs are permissive to HIV infection, initial cellular priming by gp120 results in increased expression of CXCR4 and could lead to co-receptor switching and cell tropism changes in chronic HIV infection and may have implications against CCR5-knockout based HIV cure strategies. 相似文献18.
Xiu-Mei Wang Shi-Chao Fan Yao Chen Xiao-Feng Ma Rong-Qiao He 《Biochimica et Biophysica Acta (BBA)/General Subjects》2019,1863(2):379-383
Background
Earthworms are widely used in basic and applied research in medicine, food, environment and agriculture, in which for instance earthworm protease has its own biochemical features.Scope of review
This review summarizes earthworm protease biochemical features in anti-thrombosis and anti-fibrosis, and provides new perspectives for earthworm to be used in biochemical and pharmaceutical studies.Major conclusions
Earthworm protease functions in anti-thrombosis by its fibrinolytic activity and inhibiting platelets aggregation, and anti-fibrosis by its decreasing fibronectin, collagen and laminin, showing a broad substrate specificity. The protease regulators (U3EE) from earthworm also has multiple functions acting as an activator and an inhibitor on different target proteins. Nonetheless, the protease improves the substrate selectivity through substrate-induced changes in the protease active site conformation impact on subsequent reactions with substrates.General significance
It is predictable that both biochemical and applied studies of earthworm proteins including protease will be wider and deeper in the future. 相似文献19.
Basavraj Khanppnavar Saumen Datta 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(9):2090-2103
Background
The nucleotidyl cyclase toxin ExoY is an important virulence determinant of Pseudomonas aeruginosa that causes severe acute and chronic infections in immune-compromised individuals. Additionally, this unique T3SS effector shows a striking preference for cUMP, a newly identified non-canonical secondary messenger. Thereby, ExoY is also considered as a potential tool to study unexplored cUMP signaling pathways.Methods
The crystal structure of ExoY was determined at 2.2?Å resolutions by in-situ proteolysis assisted crystallization and Rosetta-molecular replacement method. Additionally, isothermal calorimetric (ITC) and molecular dynamic (MD) simulation studies were also carried out to gain molecular insights into its substrate specificity and catalysis.Results and conclusion
ExoY is a partially unfolded protein with higher propensity to form soluble higher-order oligomers. However, with meticulous attempts of removing of disordered regions by proteases, the recalcitrant ExoY could be successfully crystallized. The crystal structure of ExoY revealed similar overall structural fold present in other anthrax toxA family of nucleotidyl cyclases, with two-to-three distinctly conserved regions conferring specificity to eukaryotic binding partner. The in-vitro catalytic preference of ExoY is in the following order: cGMP > cUMP > cAMP > cCMP. The substrate specificity of ExoY mainly depends on its ability to bind NTP in proper geometrical orientations. ExoY also seems to prefer one-metal-ion dependent catalysis than two-metal-ion dependent catalysis.General significance
Our results provide much needed structural insight on ExoY, an important virulence determinant of Pseudomonas aeruginosa and an exciting tool to study non-canonical cNMP signaling pathways.Accession numbers
The structure factors and coordinate files have been deposited in the Protein Data Bank with accession number 5XNW. 相似文献20.
Sheng-Wei Chang Jack Wellmerling Xiaoli Zhang Rachael E. Rayner Wissam Osman Sara Mertz Amal O. Amer Mark E. Peeples Prosper N. Boyaka Estelle Cormet-Boyaka 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(9):1988-1994