Carbonic anhydrase activators: Activation of the β-carbonic anhydrases from the pathogenic fungi Candida albicans and Cryptococcus neoformans with amines and amino acids

ABSTRACTSimilarities in fungal and animal cells make antifungal discovery efforts more difficult than those for other classes of antimicrobial drugs. Currently, there are only three major classes of antifungal drugs used for the treatment of systemic fungal diseases: polyenes, azoles, and echinocandins. Even in situations where the offending fungal organism is susceptible to the available drugs, treatment courses can be lengthy and unsatisfactory, since eradication of infection is often very difficult, especially in individuals with impaired immunity. Consequently, there is a need for new and more effective antifungal drugs. We have identified compounds with significant antifungal activity in the Malaria Box (Medicines for Malaria Ventures, Geneva, Switzerland) that have higher efficacy than some of the currently used antifungal drugs. Our best candidate, MMV665943 (IUPAC name 4-[6-[[2-(4-aminophenyl)-3H-benzimidazol-5-yl]methyl]-1H-benzimidazol-2-yl]aniline), here referred to as DM262, showed 16- to 32-fold-higher activity than fluconazole againstCryptococcus neoformans. There was also significant antifungal activity in other fungal species with known antifungal resistance, such asLomentospora prolificansandCryptococcus gattii. Antifungal activity was also observed against a common fungus,Candida albicans. These results are important because they offer a potentially new class of antifungal drugs and the repurposing of currently available therapeutics.IMPORTANCEMuch like the recent increase in drug-resistant bacteria, there is a rise in antifungal-resistant strains of pathogenic fungi. There is a need for novel and more potent antifungal therapeutics. Consequently, we investigated a mixed library of drug-like and probe-like compounds with activity inPlasmodiumspp. for activity against two common fungal pathogens,Cryptococcus neoformansandCandida albicans, along with two less common pathogenic species,Lomentospora prolificansandCryptococcus gattii. We uncover a previously uncharacterized drug with higher broad-spectrum antifungal activity than some current treatments. Our findings may eventually lead to a compound added to the arsenal of antifungal therapeutics.

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Antifungal Activity of the Essential Oil of Echinops kebericho Mesfin: An In Vitro Study

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2020/3101324 ◽

2020 ◽

Vol 2020 ◽

pp. 1-7

Author(s):

Tamirat Bekele Beressa ◽

Serawit Deyno ◽

Paul E. Alele

Keyword(s):

Candida Albicans ◽

Antifungal Activity ◽

Essential Oil ◽

Cryptococcus Neoformans ◽

Antioxidant Properties ◽

Pathogenic Fungi ◽

Diffusion Method ◽

Potential Candidate ◽

Standard Drug

Background. Echinops kebericho is an endemic medicinal plant in Ethiopia widely used in the treatment of infectious and noninfectious diseases. Essential oils are known for their antibacterial, antifungal, antiviral, insecticidal, and antioxidant properties. This study evaluated the antifungal activity of essential oil from E. kebericho against four common pathogenic fungi and two standard strains. Methods. The essential oil was obtained by hydrodistillation. The antifungal screening was done by agar well diffusion method. Minimal inhibitory concentrations (MICs) were determined by broth microdilution. Minimal fungicidal concentrations (MFCs) were determined by subculturing fungal strains with no visible growth onto a Sabouraud dextrose agar (SDA) plate. Results. Candida albicans and Cryptococcus neoformans were highly sensitive while Aspergillus flavus did not show sensitivity up to 1 mg/ml of essential oil; MICs ranged from 0.083 mg/ml to 0.208 mg/ml. Concentration and fungal species showed significant dose-dependent associations ( p < 0.0001 ) with antifungal activity. The MICs of essential oil were comparable to those of the standard drug (fluconazole) against C. glabrata and C. krusei. The lowest MFC of the essential oil was observed against Candida parapsilosis (0.145 mg/ml) while the highest MFC was against Candida krusei (0.667 mg/ml). Conclusion. Echinops kebericho essential oil showed noteworthy antifungal activity against Cryptococcus neoformans, Candida albicans, and Candida glabrata and could be a potential candidate for further antifungal drug development.

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Benzenesulfonamides incorporating nitrogenous bases show effective inhibition of β-carbonic anhydrases from the pathogenic fungi Cryptococcus neoformans, Candida glabrata and Malassezia globosa

Bioorganic Chemistry ◽

10.1016/j.bioorg.2019.01.030 ◽

2019 ◽

Vol 86 ◽

pp. 39-43 ◽

Cited By ~ 2

Author(s):

Silvia Bua ◽

Sameh M. Osman ◽

Zeid AlOthman ◽

Claudiu T. Supuran ◽

Alessio Nocentini

Keyword(s):

Cryptococcus Neoformans ◽

Candida Glabrata ◽

Pathogenic Fungi ◽

Carbonic Anhydrases ◽

Malassezia Globosa ◽

Effective Inhibition

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Carbonic anhydrase activators: Activation of the archaeal β-class (Cab) and γ-class (Cam) carbonic anhydrases with amino acids and amines

Bioorganic & Medicinal Chemistry Letters ◽

10.1016/j.bmcl.2008.10.005 ◽

2008 ◽

Vol 18 (23) ◽

pp. 6194-6198 ◽

Cited By ~ 26

Author(s):

Alessio Innocenti ◽

Sabrina A. Zimmerman ◽

Andrea Scozzafava ◽

James G. Ferry ◽

Claudiu T. Supuran

Keyword(s):

Amino Acids ◽

Carbonic Anhydrase ◽

Carbonic Anhydrases

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Pathogenic Yeasts Cryptococcus neoformans and Candida albicans Produce Immunomodulatory Prostaglandins

Infection and Immunity ◽

10.1128/iai.69.5.2957-2963.2001 ◽

2001 ◽

Vol 69 (5) ◽

pp. 2957-2963 ◽

Cited By ~ 153

Author(s):

Mairi C. Noverr ◽

Susan M. Phare ◽

Galen B. Toews ◽

Michael J. Coffey ◽

Gary B. Huffnagle

Keyword(s):

Candida Albicans ◽

Fungal Infection ◽

Cryptococcus Neoformans ◽

Mammalian Cells ◽

Pathogenic Fungi ◽

Host Cells ◽

Cyclooxygenase Inhibitors ◽

Fungal Colonization ◽

Chemokine Production ◽

Prostaglandin Production

ABSTRACT Enhanced prostaglandin production during fungal infection could be an important factor in promoting fungal colonization and chronic infection. Host cells are one source of prostaglandins; however, another potential source of prostaglandins is the fungal pathogen itself. Our objective was to determine if the pathogenic yeastsCryptococcus neoformans and Candida albicansproduce prostaglandins and, if so, to begin to define the role of these bioactive lipids in yeast biology and disease pathogenesis. C. neoformans and C. albicans both secreted prostaglandins de novo or via conversion of exogenous arachidonic acid. Treatment with cyclooxygenase inhibitors dramatically reduced the viability of the yeast and the production of prostaglandins, suggesting that an essential cyclooxygenase like enzyme may be responsible for fungal prostaglandin production. A PGE series lipid was purified from both C. albicans and C. neoformans and was biologically active on both fungal and mammalian cells. Fungal PGEx and synthetic PGE2 enhanced the yeast-to-hypha transition in C. albicans. Furthermore, in mammalian cells, fungal PGEx down-modulated chemokine production, tumor necrosis factor alpha production, and splenocyte proliferation while up-regulating interleukin 10 production. These are all activities previously documented for mammalian PGE2. Thus, eicosanoids are produced by pathogenic fungi, are critical for growth of the fungi, and can modulate host immune functions. The discovery that pathogenic fungi produce and respond to immunomodulatory eicosanoids reveals a virulence mechanism that has potentially great implications for understanding the mechanisms of chronic fungal infection, immune deviation, and fungi as disease cofactors.

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Cellular Localization of Carbonic Anhydrase Nce103p in Candida albicans and Candida parapsilosis

International Journal of Molecular Sciences ◽

10.3390/ijms21030850 ◽

2020 ◽

Vol 21 (3) ◽

pp. 850

Author(s):

Jiří Dostál ◽

Jan Blaha ◽

Romana Hadravová ◽

Martin Hubálek ◽

Olga Heidingsfeld ◽

...

Keyword(s):

Cell Wall ◽

Candida Albicans ◽

Carbonic Anhydrase ◽

Cellular Localization ◽

Candida Parapsilosis ◽

Growth Conditions ◽

Carbonic Anhydrases ◽

Atmospheric Conditions ◽

Low Co2 ◽

Mitochondrial Fractions

Pathogenic yeasts Candida albicans and Candida parapsilosis possess a ß-type carbonic anhydrase Nce103p, which is involved in CO2 hydration and signaling. C. albicans lacking Nce103p cannot survive in low CO2 concentrations, e.g., in atmospheric growth conditions. Candida carbonic anhydrases are orthologous to the Saccharomyces cerevisiae enzyme, which had originally been detected as a substrate of a non-classical export pathway. However, experimental evidence on localization of C. albicans and C. parapsilosis carbonic anhydrases has not been reported to date. Immunogold labeling and electron microscopy used in the present study showed that carbonic anhydrases are localized in the cell wall and plasmatic membrane of both Candida species. This localization was confirmed by Western blot and mass spectrometry analyses of isolated cell wall and plasma membrane fractions. Further analysis of C. albicans and C. parapsilosis subcellular fractions revealed presence of carbonic anhydrases also in the cytosolic and mitochondrial fractions of Candida cells cultivated in shaken liquid cultures, under the atmospheric conditions.

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Cryptococcus neoformans Senses CO2 through the Carbonic Anhydrase Can2 and the Adenylyl Cyclase Cac1

Eukaryotic Cell ◽

10.1128/ec.5.1.103-111.2006 ◽

2006 ◽

Vol 5 (1) ◽

pp. 103-111 ◽

Cited By ~ 125

Author(s):

Estelle Gewiss Mogensen ◽

Guilhem Janbon ◽

James Chaloupka ◽

Clemens Steegborn ◽

Man Shun Fu ◽

...

Keyword(s):

Carbonic Anhydrase ◽

Adenylyl Cyclase ◽

Cryptococcus Neoformans ◽

Fungal Pathogen ◽

Natural Habitat ◽

Physiological Role ◽

Immunocompromised Patients ◽

Structural Studies ◽

Carbonic Anhydrases ◽

Spontaneous Reaction

ABSTRACT Cryptococcus neoformans, a fungal pathogen of humans, causes fatal meningitis in immunocompromised patients. Its virulence is mainly determined by the elaboration of a polysaccharide capsule surrounding its cell wall. During its life, C. neoformans is confronted with and responds to dramatic variations in CO2 concentrations; one important morphological change triggered by the shift from its natural habitat (0.033% CO2) to infected hosts (5% CO2) is the induction of capsule biosynthesis. In cells, CO2 is hydrated to bicarbonate in a spontaneous reaction that is accelerated by carbonic anhydrases. Here we show that C. neoformans contains two β-class carbonic anhydrases, Can1 and Can2. We further demonstrate that CAN2, but not CAN1, is abundantly expressed and essential for the growth of C. neoformans in its natural environment, where CO2 concentrations are limiting. Structural studies reveal that Can2 forms a homodimer in solution. Our data reveal Can2 to be the main carbonic anhydrase and suggest a physiological role for bicarbonate during C. neoformans growth. Bicarbonate directly activates the C. neoformans Cac1 adenylyl cyclase required for capsule synthesis. We show that this specific activation is optimal at physiological pH.

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Amino Acids as Building Blocks for Carbonic Anhydrase Inhibitors

10.20944/preprints201805.0145.v1 ◽

2018 ◽

Author(s):

Niccolò Chiaramonte ◽

Maria Novella Romanelli ◽

Elisabetta Teodori ◽

Claudiu Supuran

Keyword(s):

Organic Chemistry ◽

Amino Acids ◽

Carbonic Anhydrase ◽

Chemical Properties ◽

Building Blocks ◽

Carbonic Anhydrases ◽

Carbonic Anhydrase Inhibitors ◽

Physiological Processes ◽

Long Time ◽

Reversible Hydration

Carbonic Anhydrases (CAs) are a superfamily of metalloenzymes widespread in all life kingdoms, classified into seven genetically different families (α-θ). These enzymes catalyse the reversible hydration of carbonic anhydride (CO2), generating bicarbonate (HCO3-) and protons (H+). Fifteen isoforms of human CA (hCA I-XV) have been isolated, their presence being fundamental for the regulation of many physiological processes. In addition, overexpression of some isoforms has been associated with the outbreak or the progression of several diseases. For this reason, for a long time CA inhibitors (CAIs) are used in the control of glaucoma and as diuretics. Furthermore, the search for new potential CAIs for other pharmacological applications is a very active field. Amino acids constitute the smallest fundamental monomers of protein and, due to their useful bivalent chemical properties, are widely used in organic chemistry. Both proteinogenic and non-proteinogenic amino acids have been extensively used to synthesize CAIs. This article provides an overview of the different strategies that have been used to design new CAIs containing amino acids, and how these bivalent molecules influence the properties of the inhibitors.

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