Appl Microbiol Biotechnol
November 2022
The last decade has witnessed the rise of an extremely threatening healthcare-associated multidrug-resistant non-albicans Candida (NAC) species, Candida auris. Since besides target alterations, efflux mechanisms contribute maximally to antifungal resistance, it is imperative to investigate their contributions in this pathogen. Of note, within the major facilitator superfamily (MFS) of efflux pumps, drug/H antiporter family 1 (DHA1) has been established as a predominant contributor towards xenobiotic efflux.
View Article and Find Full Text PDFAntifungal resistance mediated by overexpression of ABC transporters is one of the primary roadblocks to effective therapy against Candida infections. Thus, identification and characterization of the ABC transporter repertoire in Candida species are of high relevance. The method described in the chapter is based on our previously developed bioinformatic pipeline for identification of ABC proteins in Candida species.
View Article and Find Full Text PDFVH, i.e., VH domains of camelid single-chain antibodies, are very promising therapeutic agents due to their significant physicochemical advantages compared to classical mammalian antibodies.
View Article and Find Full Text PDFBiochim Biophys Acta Biomembr
August 2021
In view of the multiple clinical and physiological implications of ABC transporter proteins, there is a considerable interest among researchers to characterize them functionally. However, such characterizations are based on the premise that ABC proteins are accurately identified in the proteome of an organism, and their topology is correctly predicted. With this objective, we have developed ABC-finder, i.
View Article and Find Full Text PDFBiochim Biophys Acta Proteins Proteom
July 2021
COVID-19, caused by Severe Acute Respiratory Syndrome Corona Virus 2, is declared a Global Pandemic by WHO in early 2020. In the present situation, though more than 180 vaccine candidates with some already approved for emergency use, are currently in development against SARS-CoV-2, their safety and efficacy data is still in a very preliminary stage to recognize them as a new treatment, which demands an utmost emergency for the development of an alternative anti-COVID-19 drug for a COVID-19 free world. Since RNA-dependent RNA polymerase (RdRp) is an essential protein involved in replicating the virus, it can be held as a potential drug target.
View Article and Find Full Text PDFATP-binding cassette (ABC) superfamily members have a key role as nutrient importers and exporters in bacteria. However, their role as drug exporters in eukaryotes brought this superfamily member to even greater prominence. The capacity of ABC transporters to efflux a broad spectrum of xenobiotics represents one of the major mechanisms of clinical multidrug resistance in pathogenic fungi including species.
View Article and Find Full Text PDFSynaptosomal-associated protein of 23 kDa (SNAP-23) plays an important role during regulated exocytosis of various inflammatory mediators, stored in secretory granules, from mast cells in response to physiological triggers. It is however synthesized as a soluble protein, and the mechanisms by which free SNAP-23 gets peripherally associated with membrane for the regulation of exocytosis, are poorly defined. SNAP-23 contains a hydrophobic domain with five closely spaced cysteines which get palmitoylated, and we show that SNAP-23 cysteine mutants show differential membrane association when transfected in rat basophilic leukemia (RBL) mast cells.
View Article and Find Full Text PDFABC transporters are membrane-bound pumps composed of two major domains: the transmembrane domain(s) (TMDs) and the nucleotide-binding domain(s) (NBDs). Sequence analyses of the NBDs of key ABC exporters revealed a residue position within the H-loop to be differentially conserved in the ABCG family, wherein there lies glutamine instead of positively charged arginine/lysine as in non-ABCG members. Consequently, contrasting NBD sequences of fungal Pleiotropic Drug Resistance transporters (PDR/ABCG) with that of Cholesterol/Phospholipid and Retinal (CPR/ABCA) Flippase family revealed a high Cumulative Relative Entropy (CRE) score of this residue position implying its family-specific functional significance.
View Article and Find Full Text PDFABC transporter proteins are involved in active transport, both in prokaryotes and eukaryotes. Sequence analysis of nucleotide binding domains (NBDs) of ABC proteins from all taxa revealed a well-conserved new motif having the signature: xT/ShxE/DNhxF, located between Q-loop and ABC signature sequence. A recent structure of an ABC transporter, ABCG5/G8 highlighted the motif as an essential structural determinant of inter-domain crosstalk and termed it as E-helix.
View Article and Find Full Text PDFMajor facilitator superfamily is one of the largest superfamily of secondary transporters present across the kingdom of life. Considering the physiological and clinical importance of MFS proteins, we attempted to explore the phylogenetic and structural aspects of the superfamily. To achieve the objectives, we performed global sequence-based analyses of MFS proteins encompassing multiple taxa.
View Article and Find Full Text PDFProteins of the SNARE (Soluble N-ethylmaleimide-sensitive factor attachment protein receptors) family play a significant role in all vesicular fusion events involved in endocytic and exocytic pathways. These proteins act as molecular machines that assemble into tight four-helix bundle complex, bridging the opposing membranes into close proximity forming membrane fusion. Almost all SNARE proteins share a 53 amino acid coiled-coil domain, which is mostly linked to the transmembrane domain at the C-terminal end.
View Article and Find Full Text PDFATP-binding cassette (ABC) is one of the two major superfamilies of transporters present across the evolutionary scale. ABC superfamily members came to prominence due to their ability to extrude broad spectrum of substrates and to confer multi drug resistance (MDR). Overexpression of some ABC transporters in clinical isolates of Candida species was attributed to the development of MDR phenotypes.
View Article and Find Full Text PDFATP-binding cassette (ABC) is one of the largest superfamily of proteins, which are ubiquitously present, performing variety of cellular functions. These proteins as drug transporters have been enticing substantial consideration because of their clinical importance. The present study focuses on genome wide identification of ABC proteins of an important halotolerant yeast Debaryomyces hansenii and explores their role in salt and drug tolerance.
View Article and Find Full Text PDFMisfolding and aggregation of Cu, Zn Superoxide Dismutase (SOD1) is often found in amyotrophic lateral sclerosis (ALS) patients. The central apo SOD1 barrel was involved in protein maturation and pathological aggregation in ALS. In this work, we employed atomistic molecular dynamics (MD) simulations to study the conformational dynamics of SOD1 monomer in different concentrations of trifluoroethanol (TFE).
View Article and Find Full Text PDFHuman carbonic anhydrase IX (CAIX) has evolved as a promising biomarker for cancer prognosis, due to its overexpression in various cancers and restricted expression in normal tissue. However, limited information is available on its biophysical behavior. The unfolding of CAIX in aqueous urea solution was studied using all-atom molecular dynamics simulation approach.
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