Biology subjects

Perez Carrillo, V. H.

Publications and source records attributed to Perez Carrillo, V. H..

3 recordsLinked to original sources

bioRxiv2025

Bidirectional communication between nucleotide and substrate binding sites in a type IV multidrug ABC transporter

ATP-binding cassette (ABC) transporters use ATP to transport substrates across cellular membranes. In type IV ABC transporters, including many multidrug resistance (MDR) pumps, communication between the nucleotide-binding domains (NBDs) and transmembrane domains (TMDs) occurs via intracellular coupling helices. However, the precise mechanism of interdomain crosstalk and coordination between the ATP and substrate binding sites remain unclear. Combining nuclear magnetic resonance (NMR) spectroscopy, Hydrogen-Deuterium eXchange Mass Spectrometry (HDX-MS), photo-induced electron-transfer fluorescence correlation spectroscopy (PET-FCS) and functional assays, we identified a conserved cluster of residues at the NBD/TMD interface of the bacterial MDR transporter BmrA. This cluster is crucial for transporter function and relays nucleotide and substrate binding between the two domains via coupling helix 2. Mutations impact both local and global transporter dynamics. Our findings reveal a novel interdomain communication pathway in type IV ABC transporters, shedding light on the intricate coupling mechanisms that enable the coordination of these molecular machines.

biophysics↗

bioRxiv2024

Effect of 2,4-Dinitrophenol Against Multidrug-Resistant Bacteria

Multidrug-resistant bacteria have become very important in recent decades due to the health problems they cause. Different mechanisms of resistance in bacteria have been identified among which are efflux pumps. It is believed that chemical compounds such as 2,4-dinitrophenol (2,4-DNP) can inhibit efflux pumps which normally participate in detoxifying cells. In the present work antibiotic multiresistant cells were isolated. Resistance of these bacteria to different antibiotics was tested by the Kirby-Bauer method and ethidium bromide tolerance. It was assumed that they showed overexpression of efflux pumps. The effect of 2,4-DNP was tested and the antibiotic resistance and growth of the cells were measured. Although a strong inhibition effect by 2,4-DNP was observed, an unexpected variation in MICs among the samples suggests that 2,4DNP has a more complex effect on bacteria than originally assumed.

microbiology↗

bioRxiv2023

Legionella pneumophila macrophage infectivity potentiator protein appendage domains modulate protein dynamics and inhibitor binding

Macrophage infectivity potentiator (MIP) proteins are widespread in human pathogens including Legionella pneumophila, the causative agent of Legionnaires disease and protozoans such as Trypanosoma cruzi. All MIP proteins contain a FKBP (FK506 binding protein)-like prolyl-cis/trans- isomerase domain that hence presents an attractive drug target. Some MIPs such as the Legionella pneumophila protein (LpMIP) have additional appendage domains of mostly unknown function. In full- length, homodimeric LpMIP, the N-terminal dimerization domain is linked to the FKBP-like domain via a long, free-standing stalk helix. Combining X-ray crystallography, NMR and EPR spectroscopy and SAXS, we elucidated the importance of the stalk helix for protein dynamics and inhibitor binding to the FKBP-like domain and bidirectional crosstalk between the different protein regions. The first comparison of a microbial MIP and a human FKBP in complex with the same synthetic inhibitor was made possible by high-resolution structures of LpMIP with a [4.3.1]-aza-bicyclic sulfonamide and provides a basis for designing pathogen-selective inhibitors. Through stereospecific methylation, the affinity of inhibitors to L. pneumophila and T. cruzi MIP was greatly improved. The resulting X-ray inhibitor-complex structures of LpMIP and TcMIP at 1.49 and 1.34 [A], respectively, provide a starting point for developing potent inhibitors against MIPs from multiple pathogenic microorganisms.

biophysics↗