A5022221620- Bacterial Genetics and Biotechnology
- Protein Structure and Dynamics
- Photosynthetic Processes and Mechanisms
- Bacteriophages and microbial interactions
- Mitochondrial Function and Pathology
- ATP Synthase and ATPases Research
- Antibiotic Resistance in Bacteria
- Alkaline Phosphatase Research Studies
- Glycosylation and Glycoproteins Research
- Biochemical and Molecular Research
- Monoclonal and Polyclonal Antibodies Research
- Cancer Research and Treatments
- Plant Pathogenic Bacteria Studies
- Enzyme Structure and Function
- Folate and B Vitamins Research
- RNA and protein synthesis mechanisms
- Legume Nitrogen Fixing Symbiosis
- Pancreatitis Pathology and Treatment
- RNA Interference and Gene Delivery
- Liver Disease Diagnosis and Treatment
- Fungal and yeast genetics research
- Microbial Natural Products and Biosynthesis
- Biofuel production and bioconversion
- Plant-Microbe Interactions and Immunity
- Metabolism and Genetic Disorders
Foundation for Research and Technology Hellas
2001-2021
FORTH Institute of Molecular Biology and Biotechnology
1995-2021
University of Crete
2001-2006
Institute of Molecular Biology and Biotechnology
2000
Oxidative protein folding in the mitochondrial intermembrane space requires transfer of a disulfide bond from MIA40 to substrate. During this process is reduced and regenerated functional state through interaction with flavin-dependent sulfhydryl oxidase ALR. Here we present mechanistic basis ALR–MIA40 at atomic resolution by biochemical structural analyses ALR isoform its covalent mixed intermediate MIA40. This contains folded FAD-binding domain C-terminus an unstructured, flexible...
The gene encoding alkaline phosphatase (AP) from the psychrophilic strain TAB5 was cloned, and its nucleotide sequence determined. A single open reading frame consisting of 1125 base pairs which encodes a polypeptide signal peptide 22 amino acids mature protein 353 identified. deduced AP exhibits 38% identity to III IV sequences Bacillus subtilis conserves typical motifs core structure active sites APs various sources. Based on crystal mutated Escerichia coli D153H, homology‐based 3D model...
Summary The specialized type III secretion (T3S) apparatus of pathogenic and symbiotic Gram‐negative bacteria comprises a complex transmembrane organelle an ATPase homologous to the F 1 ‐ATPase β subunit. T3S HrcN Pseudomonas syringae associates with inner membrane, its ATP hydrolytic activity is stimulated by dodecamerization. structure dodecameric (HrcN 12 ) determined 1.6 nm cryo‐electron microscopy presented. two hexameric rings that are probably stacked face‐to‐face association their...
Erv1 and Mia40 constitute the two important components of disulfide relay system that mediates oxidative protein folding in mitochondrial intermembrane space. is import receptor recognizes substrates introducing bonds while it reduced. A key function to recycle its active state. Our aims here were dissect domain protein–protein interaction with investigate interactions between shuttle catalytic core their relevance for Mia40. We purified these domains separately as well cysteine mutants...
The interaction of Mia40 with Erv1/ALR is central to the oxidative protein folding in intermembrane space mitochondria (IMS) as oxidizes reduced restore its functional state. Here we address role import and maturation Erv1/ALR. C-terminal FAD-binding domain has an essential process by creating a transient intermolecular disulfide bond Mia40. action selective for formation both intra intersubunit structural bonds Erv1/ALR, but complete requires additional binding FAD. Both these events must...
Terminal residues in SecA, the dimeric ATPase motor of bacterial preprotein translocase, were proposed to be required for function and dimerization. To test this, we generated truncation mutants 901aa long SecA Escherichia coli. We now show that deletions carboxy-terminal domain (CTD), extreme CTD 70 residues, or N-terminal nonapeptide both, do not compromise protein translocation viability. Deletion additional C-terminal upstream compromised function. Functional like SecA9-861 are dimeric,...
Novel biophysical tools allow the structural dynamics of proteins and regulation such by binding partners to be explored in unprecedented detail. Although this has provided critical insights into protein function, means which direct evolution remain poorly understood. Here, we investigated how with a bilobed structure, composed two related domains from periplasmic-binding protein-like II domain family, have undergone divergent evolution, leading adaptation their dynamics. We performed...
We evaluated the feasibility of large-scale production biopharmaceuticals expressed as heterologous polypeptides from Gram-positive bacterium Streptomyces lividans. As a model protein we used murine tumor necrosis factor alpha (mTNFα). mTNFα fused C-terminally to secretory signal peptide subtilisin-inhibitor venezuelae. Under appropriate fermentation conditions, significant amounts mature (80–120 mg/L) can be recovered spent growth media. Efficient downstream processing allowing rapid...
In an effort to explore the effects of local flexibility on cold adaptation enzymes, we designed point mutations aiming modify side‐chain at active site psychrophilic alkaline phosphatase from Antarctic strain TAB5. The mutagenesis targets were residues Trp260 and Ala219 catalytic His135 Mg 2+ binding site. replacement by Lys in mutant W260K, resulted enzyme less than wild‐type temperature range 5–25 °C. additional Asn double W260K/A219N, a drastic increase energy activation, which was...
The discovery of the mitochondrial intermembrane space assembly (MIA) pathway was followed by studies that focused mainly on typical small substrates this disulfide relay system and interactions between its two central partners: oxidoreductase Mia40 FAD-protein Erv1. Recent have revealed more complex proteins utilize pathway, including itself. In present study, we dissect biogenesis in distinct stages, supporting a kinetically coordinated sequence events, starting with (a) import insertion...
Recurrent protein folding motifs include various types of helical bundles formed by α-helices that supercoil around each other. While specific patterns amino acid residues (heptad repeats) characterize the highly versatile motif four-α-helical bundles, significance polypeptide chain directionality is not sufficiently understood, although it determines sequence patterns, dipoles, and other parameters for oligomerization processes bundles. To investigate aspects in sequence-structure...
ABSTRACT Many plant-pathogenic bacteria of considerable economic importance rely on type III secretion systems (T3SSs) the Hrc-Hrp 1 family to subvert their plant hosts. T3SS gene expression is regulated through HrpG and HrpV proteins, while controlled by gatekeeper HrpJ. A link between two mechanisms was so far unknown. Here, we show that a mechanistic coupling exists cascades direct binding HrpG/HrpV heterodimer, acting as chaperone, The ternary complex docked cytoplasmic side inner...
We evaluated the feasibility of large-scale production biopharmaceuticals expressed as heterologous polypeptides from Gram-positive bacterium Streptomyces lividans. As a model protein we used murine tumor necrosis factor alpha (mTNFα). mTNFα fused C-terminally to secretory signal peptide subtilisin-inhibitor venezuelae. Under appropriate fermentation conditions, significant amounts mature (80–120 mg/L) can be recovered spent growth media. Efficient downstream processing allowing rapid...
Conference Abstract| October 01 2000 ATP catalysis by the protein translocase machine E. Vrontou; Vrontou 1IMBB, PO Box 1527, 711 10 Iraklio, Crete, GREECE Search for other works this author on: This Site PubMed Google Scholar G. Sianidis; Sianidis C. Baud; Baud A. S. Politou; Politou Pozidis; Pozidis Y. Papanikolau; Papanikolau Karamanou; Karamanou Economou Biochem Soc Trans (2000) 28 (5): A116. https://doi.org/10.1042/bst028a116a Views Icon Article contents Figures & tables Video Audio...