Publications by authors named "Carrie Lomelino"

It has been previously established that breast cancer cells exhibit high expression of the monocarboxylate (lactate) transporters (MCT1 and/or MCT4) and carbonic anhydrase IX (CAIX) and form a functional metabolon for proton-coupled lactate export, thereby stabilizing intracellular pH. CD147 is the MCT accessory protein that facilitates the creation of the MCT/CAIX complex. This study describes how the small molecule Beta-Galactose 2C (BGal2C) blocks the physical and functional interaction between CAIX and either MCT1 or MCT4 in Xenopus oocytes, which reduces the rate of proton and lactate flux with an IC of ~90 nM.

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The combination of X-ray free-electron lasers (XFELs) with serial femtosecond crystallography represents cutting-edge technology in structural biology, allowing the study of enzyme reactions and dynamics in real time through the generation of `molecular movies'. This technology combines short and precise high-energy X-ray exposure to a stream of protein microcrystals. Here, the XFEL structure of carbonic anhydrase II, a ubiquitous enzyme responsible for the interconversion of CO and bicarbonate, is reported, and is compared with previously reported NMR and synchrotron X-ray and neutron single-crystal structures.

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We report a one-pot procedure for the synthesis of asymmetrical ureido-containing benzenesulfonamides based on in situ generation of the corresponding isocyanatobenezenesulfonamide species, which were trapped with the appropriate amines. A library of new compounds was generated and evaluated in vitro for their inhibition properties against a representative panel of the human (h) metalloenzymes carbonic anhydrases (EC 4.2.

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The "tail approach" has become a milestone in human carbonic anhydrase inhibitor (hCAI) design for various therapeutics, including antiglaucoma agents. Besides the classical hydrophobic/hydrophilic division of hCAs active site, several subpockets have been identified at the middle/outer active sites rim, which could be targeted to increase the CAI isoform selectivity. This postulate is explored here by three-tailed benzenesulfonamide CAIs () to fully exploit such amino acid differences among hCAs.

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The integrity of cellular genome is continuously challenged by endogenous and exogenous DNA damaging agents. If DNA damage is not removed in a timely fashion the replisome may stall at DNA lesions, causing fork collapse and genetic instability. Base excision DNA repair (BER) is the most important pathway for the removal of oxidized or mono-alkylated DNA.

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Carbonic anhydrases (CAs) are molecular targets in various diseases. While many sulfonamide-based drugs are in clinical use, CA inhibitor design is moving towards the incorporation of alternative zinc-binding groups, such as carboxylic acids, to promote CA isoform-specific inhibition. Here, X-ray crystal structures of CA II in complex with nicotinic acid and ferulic acid determined to 1.

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Swine represent the only livestock with an established invariant NKT (iNKT) cell-CD1d system. In this study, we exploited the fact that pig iNKT cells can be purified using a mouse CD1d tetramer reagent to establish their TCR repertoire by next generation sequencing. CD1d tetramer-positive pig cells predominantly expressed an invariant Vα-Jα rearrangement, without nontemplate nucleotide diversity, homologous to the Vα24-Jα18 and Vα14-Jα18 rearrangements of human and murine iNKT cells.

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X-ray and neutron crystallography are powerful techniques utilized to study the structures of biomolecules. Visualization of enzymes in complex with substrate/product and the capture of intermediate states can be related to activity to facilitate understanding of the catalytic mechanism. Subsequent analysis of small molecule binding within the enzyme active site provides insight into mechanisms of inhibition, supporting the design of novel inhibitors using a structure-guided approach.

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Carbonic anhydrase IX (CA IX) expression is important for the regulation of pH in hypoxic tumors and is emerging as a therapeutic target for the treatment of various cancers. Recent studies have demonstrated the selectivity of sucrose, saccharin, and acesulfame potassium for CA IX over other CA isoforms. Reported here is the X-ray crystal structure of CA IX-mimic in complex with sucralose determined to ∼1.

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Article Synopsis
  • Recent advancements in X-ray free-electron lasers (XFEL) have enhanced the study of protein dynamics using femtosecond X-ray pulses to observe enzyme catalysis.
  • The research demonstrates successful growth of high-quality microcrystals of carbonic anhydrase II, essential for XFEL diffraction at the Pohang Accelerator Laboratory.
  • The microcrystals achieved a resolution of 1.7 Å and were indexed, laying the groundwork for future experiments on the dynamics of carbonic anhydrase catalysis.
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Carbonic anhydrases (CAs) catalyze the reversible hydration of carbon dioxide to produce bicarbonate and a proton. Multiple CA isoforms are implicated in a range of diseases, including cancer. In solid tumors, continuously dividing cells create hypoxic conditions that eventually lead to an acidic microenvironment.

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Carbonic anhydrase II (CA II) is a zinc metalloenzyme that catalyzes the reversible interconversion of water and CO to bicarbonate and a proton. CA II is abundant in most cells, and plays a role in numerous processes including gas exchange, epithelial ion transport, respiration, extra- and intracellular pH control, and vascular regulation. Beyond these CO and pH-linked roles, it has been postulated that CA II might also reduce nitrite (NO) to nitric oxide (NO), as bicarbonate and NO both exhibit sp molecular geometry and NO also plays an important role in vasodilation and regulation of blood pressure.

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Human carbonic anhydrase II (hCA II) is a zinc metalloenzyme that catalyzes the reversible hydration/dehydration of CO/HCO. Although hCA II has been extensively studied to investigate the proton-transfer process that occurs in the active site, its underlying mechanism is still not fully understood. Here, ultrahigh-resolution crystallographic structures of hCA II cryocooled under CO pressures of 7.

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Asparagine Synthetase Deficiency (ASD) is a recently described inborn error of metabolism caused by bi-allelic pathogenic variants in the asparagine synthetase (ASNS) gene. ASD typically presents congenitally with microcephaly and severe, often medically refractory, epilepsy. Development is generally severely affected at birth.

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Human carbonic anhydrase IX (CA IX) is upregulated in neoplastic tissues; as such, it is studied as a drug target for anticancer chemotherapy. Inhibition of CA IX has been shown to be therapeutically favorable in terms of reducing tumor growth. Previously, saccharin, a commonly used artificial sweetener, has been observed to selectively inhibit CA IX over other CA isoforms.

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Incorporation of the purine/pyrimidine moieties as tails to classical benzenesulfonamide scaffolds afforded two series of human (h) carbonic anhydrase (CA, EC 4.2.1.

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The Myxomavirus-derived protein Serp-1 has potent anti-inflammatory activity in models of vasculitis, lupus, viral sepsis, and transplant. Serp-1 has also been tested successfully in a Phase IIa clinical trial in unstable angina, representing a "first-in-class" therapeutic. Recently, peptides derived from the reactive center loop (RCL) have been developed as stand-alone therapeutics for reducing vasculitis and improving survival in MHV68-infected mice.

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Asparagine synthetase (ASNS) converts aspartate and glutamine to asparagine and glutamate in an ATP-dependent reaction. ASNS is present in most, if not all, mammalian organs, but varies widely in basal expression. Human ASNS activity is highly responsive to cellular stress, primarily by increased transcription from a single gene located on chromosome 7.

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We report the synthesis, biological evaluation, and structural study of a series of substituted heteroaryl-pyrazole carboxylic acid derivatives. These compounds have been developed as inhibitors of specific isoforms of carbonic anhydrase (CA), with potential as prototypes of a new class of chemotherapeutics. Both X-ray crystallography and computational modeling provide insights into the CA inhibition mechanism.

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Specific isoforms from the carbonic anhydrase (CA) family of zinc metalloenzymes have been associated with a variety of diseases. Isoform-specific carbonic anhydrase inhibitors (CAIs) are therefore a major focus of attention for specific disease treatments. Classical CAIs, primarily sulfonamide-based compounds and their bioisosteres, are examined as antiglaucoma, antiepileptic, antiobesity, antineuropathic pain and anticancer compounds.

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