Biology subjects

Zuccotto, F.

Publications and source records attributed to Zuccotto, F..

4 recordsLinked to original sources

bioRxiv2025

Design and development of lysyl tRNA synthetase inhibitors, for the treatment of tuberculosis

There is currently a public health crisis due to the rise of multi-drug-resistant tuberculosis cases, as well as the rise in number of deaths from tuberculosis. To achieve the United Nations Sustainable Development Goal of ending the tuberculosis epidemic by 2030, new treatments are urgently required. We previously reported the discovery of 49, a pre-clinical candidate that acted through inhibition of the Mycobacterium tuberculosis lysyl-tRNA synthetase (LysRS). In this report, the full medicinal chemistry program is reviewed from the original hit through to the optimised lead. The work was guided by the first crystal structure of M. tuberculosis LysRS. The physicochemical and pharmacokinetic properties were optimised to afford compounds suitable for evaluation in mouse efficacy models of tuberculosis and with the potential for clinical development.

microbiology↗

bioRxiv2023

Application of an NMR/crystallography fragment screening platform for the assessment and rapid discovery of new HIV-CA binding fragments

Identification and assessment of novel targets is essential to combat drug resistance in the treatment of HIV/AIDS. HIV Capsid (HIV-CA), the protein playing a major role in both the early and late stages of the viral life cycle, has emerged as an important target. We have applied an NMR fragment screening platform and identified molecules that bind to the N-terminal domain (NTD) of HIV-CA at a site close to the interface with the C-terminal domain (CTD). Using X-ray crystallography, we have been able to obtain crystal structures to identify the binding mode of these compounds. This allowed for rapid progression of the initial, weak binding, fragment starting points to compounds 37 and 38, which have 19F-pK values of 5.3 and 5.4 respectively. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=56 SRC="FIGDIR/small/569544v2_ufig1.gif" ALT="Figure 1"> View larger version (6K): org.highwire.dtl.DTLVardef@1c7043corg.highwire.dtl.DTLVardef@e73044org.highwire.dtl.DTLVardef@11c1d9org.highwire.dtl.DTLVardef@1cd99e7_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

bioRxiv2021

Molecular basis for recognition of the Group A Carbohydrate backbone by the PlyC streptococcal bacteriophage endolysin

Endolysins are peptidoglycan (PG) hydrolases that function as part of the bacteriophage (phage) lytic system to release progeny phage at the end of a replication cycle. Notably, endolysins alone can produce lysis without phage infection, which offers an attractive alternative to traditional antibiotics. Endolysins from phage that infect Gram-positive bacterial hosts contain at least one enzymatically active domain (EAD) responsible for hydrolysis of PG bonds and a cell wall binding domain (CBD) that binds a cell wall epitope, such as a surface carbohydrate, providing some degree of specificity for the endolysin. Whilst the EADs typically cluster into conserved mechanistic classes with well-defined active sites, relatively little is known about the nature of the CBDs and only a few binding epitopes for CBDs have been elucidated. The major cell wall components of many streptococci are the polysaccharides that contain the polyrhamnose (pRha) backbone modified with species-specific and serotype-specific glycosyl side chains. In this report, using molecular genetics, microscopy, flow cytometry and lytic activity assays, we demonstrate the interaction of PlyCB, the CBD subunit of the streptococcal PlyC endolysin, with the pRha backbone of the cell wall polysaccharides, Group A Carbohydrate (GAC) and serotype c-specific carbohydrate (SCC) expressed by the Group A Streptococcus and Streptococcus mutans, respectively.

biochemistry↗

bioRxiv2020

Instability of aquaglyceroporin (AQP) 2 contributes to drug resistance in Trypanosoma brucei

Defining mode of action is vital for both developing new drugs and predicting potential resistance mechanisms. African trypanosome pentamidine and melarsoprol sensitivity is predominantly mediated by aquaglyceroporin 2 (TbAQP2), a channel associated with water/glycerol transport. TbAQP2 is expressed at the flagellar pocket membrane and chimerisation with TbAQP3 renders parasites resistant to both drugs. Two models for how TbAQP2 mediates pentamidine sensitivity have emerged; that TbAQP2 mediates pentamidine translocation or via binding to TbAQP2, with subsequent endocytosis, but trafficking and regulation of TbAQPs is uncharacterised. We demonstrate that TbAQP2 is organised as a high order complex, is ubiquitylated and transported to the lysosome. Unexpectedly, mutation of potential ubiquitin conjugation sites, i.e. cytoplasmic lysine residues, reduced folding and tetramerization efficiency and triggered ER retention. Moreover, TbAQP2/TbAQP3 chimerisation also leads to impaired oligomerisation, mislocalisation, and increased turnover. These data suggest that TbAQP2 stability is highly sensitive to mutation and contributes towards emergence of drug resistance.

microbiology↗