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Kane A, Dinh H, Campbell L, Cain AK, Hibbs D, Carter D. Spectrum of activity and mechanisms of azole-bisphosphonate synergy in pathogenic Candida. Microbiol Spectr 2024; 12:e0012124. [PMID: 38695556 DOI: 10.1128/spectrum.00121-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Accepted: 04/12/2024] [Indexed: 06/06/2024] Open
Abstract
Candidiasis places a significant burden on human health and can range from common superficial vulvovaginal and oral infections to invasive diseases with high mortality. The most common Candida species implicated in human disease is Candida albicans, but other species like Candida glabrata are emerging. The use of azole antifungals for treatment is limited by increasing rates of resistance. This study explores repositioning bisphosphonates, which are traditionally used for osteoporosis, as antifungal synergists that can improve and revitalize the use of azoles. Risedronate, alendronate, and zoledronate (ZOL) were tested against isolates from six different species of Candida, and ZOL produced moderate antifungal activity and strong synergy with azoles like fluconazole (FLC), particularly in C. glabrata. FLC:ZOL combinations had increased fungicidal and antibiofilm activity compared to either drug alone, and the combination prevented the development of antifungal resistance. Mechanistic investigations demonstrated that the synergy was mediated by the depletion of squalene, resulting in the inhibition of ergosterol biosynthesis and a compromised membrane structure. In C. glabrata, synergy compromised the function of membrane-bound multidrug transporters and caused an accumulation of reactive oxygen species, which may account for its acute sensitivity to FLC:ZOL. The efficacy of FLC:ZOL in vivo was confirmed in a Galleria mellonella infection model, where combinations improved the survival of larvae infected with C. albicans and C. glabrata to a greater extent than monotherapy with FLC or ZOL, and at reduced dosages. These findings demonstrate that bisphosphonates and azoles are a promising new combination therapy for the treatment of topical candidiasis. IMPORTANCE Candida is a common and often very serious opportunistic fungal pathogen. Invasive candidiasis is a prevalent cause of nosocomial infections with a high mortality rate, and mucocutaneous infections significantly impact the quality of life of millions of patients a year. These infections pose substantial clinical challenges, particularly as the currently available antifungal treatment options are limited in efficacy and often toxic. Azoles are a mainstay of antifungal therapy and work by targeting the biosynthesis of ergosterol. However, there are rising rates of acquired azole resistance in various Candida species, and some species are considered intrinsically resistant to most azoles. Our research demonstrates the promising therapeutic potential of synergistically enhancing azoles with non-toxic, FDA-approved bisphosphonates. Repurposing bisphosphonates as antifungal synergists can bypass much of the drug development pipeline and accelerate the translation of azole-bisphosphonate combination therapy.
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Affiliation(s)
- Aidan Kane
- School of Life and Environmental Sciences and the Sydney Institute for Infectious Diseases, The University of Sydney, Sydney, New South Wales, Australia
| | - Hue Dinh
- School of Natural Sciences, ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, New South Wales, Australia
| | - Leona Campbell
- School of Life and Environmental Sciences and the Sydney Institute for Infectious Diseases, The University of Sydney, Sydney, New South Wales, Australia
| | - Amy K Cain
- School of Natural Sciences, ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, New South Wales, Australia
| | - David Hibbs
- School of Pharmacy, The University of Sydney, Sydney, New South Wales, Australia
| | - Dee Carter
- School of Life and Environmental Sciences and the Sydney Institute for Infectious Diseases, The University of Sydney, Sydney, New South Wales, Australia
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Schuster M, Kilaru S, Steinberg G. Azoles activate type I and type II programmed cell death pathways in crop pathogenic fungi. Nat Commun 2024; 15:4357. [PMID: 38821954 PMCID: PMC11143370 DOI: 10.1038/s41467-024-48157-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 04/22/2024] [Indexed: 06/02/2024] Open
Abstract
Triazoles are widely used to control pathogenic fungi. They inhibit the ergosterol biosynthetic pathway, but the precise mechanisms leading to fungicidal activities in many fungal pathogens are poorly understood. Here, we elucidate the mode of action of epoxiconazole and metconazole in the wheat pathogen Zymoseptoria tritici and the rice blast fungus Magnaporthe oryzae. We show that both azoles have fungicidal activity and reduce fluidity, but not integrity, of the plasma membrane. This impairs localisation of Cdc15-like F-BAR proteins, resulting in defective actin ring assembly and incomplete septation. However, mutant studies and pharmacological experiments in vitro and in planta show that azole lethality is due to a combination of reactive oxygen species-induced apoptosis and macroautophagy. Simultaneous inhibition of both programmed cell death pathways abolishes azole-induced cell death. Other classes of ergosterol biosynthesis inhibitors also induce apoptosis and macroautophagy, suggesting that activation of these two cell death pathways is a hallmark of ergosterol synthesis-targeting fungicides. This knowledge will inform future crop protection strategies.
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Tong Z, Meng D, Zhang W, Jin L, Yi X, Dong X, Sun M, Chu Y, Duan J. Mechanism Insights into the Enantioselective Bioactivity and Fumonisin Biosynthesis of Mefentrifluconazole to Fusarium verticillioides. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024. [PMID: 38607803 DOI: 10.1021/acs.jafc.4c01336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2024]
Abstract
The occurrence of maize ear rot caused by Fusarium verticillioides (F. verticillioides) poses a threat to the yield and quality of maize. Mefentrifluconazole enantiomers appear to have strong stereoselective activity against F. verticillioides and cause differences in fumonisin production. We evaluated the stereoselective activity of mefentrifluconazole enantiomers by determining inhibition of the strain, hyphae, and conidia. Strain inhibition by R-(-)-mefentrifluconazole was 241 times higher than S-(+)-mefentrifluconazole and 376 times higher in conidia inhibition. For the mechanism of the enantioselective bioactivity, R-mefentrifluconazole had stronger binding to proteins than S-(+)-mefentrifluconazole. Under several concentration conditions, the fumonisin concentration was 1.3-24.9-fold higher in the R-(-)-mefentrifluconazole treatment than in the S-(+)-mefentrifluconazole treatment. The R-enantiomer stimulated fumonisin despite a higher bioactivity. As the incubation time increased, the stimulation of the enantiomers on fumonisin production decreased. R-(-)-Mefentrifluconazole stimulated higher fumonisin production in F. verticillioides at 25 °C compared to 30 °C. This study established a foundation for the development of high-efficiency and low-risk pesticides.
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Affiliation(s)
- Zhou Tong
- Institute of Plant Protection and Agro-Product Safety, Anhui Academy of Agricultural Sciences, Hefei 230031, China
- Anhui Province Key Laboratory of Pesticide Resistance Management on Grain and Vegetable Pests, Hefei 230031, China
- Key Laboratory of Agro-Product Safety Risk Evaluation (Hefei), Ministry of Agriculture, Hefei 230031, China
| | - DanDan Meng
- Institute of Plant Protection and Agro-Product Safety, Anhui Academy of Agricultural Sciences, Hefei 230031, China
- Anhui Province Key Laboratory of Pesticide Resistance Management on Grain and Vegetable Pests, Hefei 230031, China
- Key Laboratory of Agro-Product Safety Risk Evaluation (Hefei), Ministry of Agriculture, Hefei 230031, China
| | - WenYu Zhang
- Institute of Plant Protection and Agro-Product Safety, Anhui Academy of Agricultural Sciences, Hefei 230031, China
- Anhui Province Key Laboratory of Pesticide Resistance Management on Grain and Vegetable Pests, Hefei 230031, China
- Key Laboratory of Agro-Product Safety Risk Evaluation (Hefei), Ministry of Agriculture, Hefei 230031, China
| | - Lei Jin
- Institute of Plant Protection and Agro-Product Safety, Anhui Academy of Agricultural Sciences, Hefei 230031, China
- Anhui Province Key Laboratory of Pesticide Resistance Management on Grain and Vegetable Pests, Hefei 230031, China
- Key Laboratory of Agro-Product Safety Risk Evaluation (Hefei), Ministry of Agriculture, Hefei 230031, China
| | - XiaoTong Yi
- Institute of Plant Protection and Agro-Product Safety, Anhui Academy of Agricultural Sciences, Hefei 230031, China
- Anhui Province Key Laboratory of Pesticide Resistance Management on Grain and Vegetable Pests, Hefei 230031, China
- Key Laboratory of Agro-Product Safety Risk Evaluation (Hefei), Ministry of Agriculture, Hefei 230031, China
| | - Xu Dong
- Institute of Plant Protection and Agro-Product Safety, Anhui Academy of Agricultural Sciences, Hefei 230031, China
- Anhui Province Key Laboratory of Pesticide Resistance Management on Grain and Vegetable Pests, Hefei 230031, China
- Key Laboratory of Agro-Product Safety Risk Evaluation (Hefei), Ministry of Agriculture, Hefei 230031, China
| | - MingNa Sun
- Institute of Plant Protection and Agro-Product Safety, Anhui Academy of Agricultural Sciences, Hefei 230031, China
- Anhui Province Key Laboratory of Pesticide Resistance Management on Grain and Vegetable Pests, Hefei 230031, China
- Key Laboratory of Agro-Product Safety Risk Evaluation (Hefei), Ministry of Agriculture, Hefei 230031, China
| | - Yue Chu
- Institute of Plant Protection and Agro-Product Safety, Anhui Academy of Agricultural Sciences, Hefei 230031, China
- Anhui Province Key Laboratory of Pesticide Resistance Management on Grain and Vegetable Pests, Hefei 230031, China
- Key Laboratory of Agro-Product Safety Risk Evaluation (Hefei), Ministry of Agriculture, Hefei 230031, China
| | - JinSheng Duan
- Institute of Plant Protection and Agro-Product Safety, Anhui Academy of Agricultural Sciences, Hefei 230031, China
- Anhui Province Key Laboratory of Pesticide Resistance Management on Grain and Vegetable Pests, Hefei 230031, China
- Key Laboratory of Agro-Product Safety Risk Evaluation (Hefei), Ministry of Agriculture, Hefei 230031, China
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Wang L, Song X, Cheng YN, Cheng S, Chen T, Li H, Yan J, Wang X, Zhou H. 1,2,4-Triazole benzamide derivative TPB against Gaeumannomyces graminis var. tritici as a novel dual-target fungicide inhibiting ergosterol synthesis and adenine nucleotide transferase function. PEST MANAGEMENT SCIENCE 2024; 80:1717-1727. [PMID: 38010196 DOI: 10.1002/ps.7900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 11/20/2023] [Accepted: 11/25/2023] [Indexed: 11/29/2023]
Abstract
BACKGROUND Isopropyl 4-(2-chloro-6-(1H-1,2,4-triazol-1-yl)benzamido)benzoate (TPB) was a 1,2,4-triazole benzoyl arylamine derivative with excellent antifungal activity, especially against Gaeumannomyces graminis var. tritici (Ggt). Its mechanism of action was investigated by transmission electron microscopy (TEM) observation, assays of sterol composition, cell membrane permeability, intracellular ATP and mitochondrial membrane potential, and mPTP permeability, ROS measurement, RNA sequencing (RNA-seq) analysis. RESULTS TPB interfered with ergosterol synthesis, reducing ergosterol content, increasing toxic intermediates, and finally causing biomembrane disruption such as increasing cell membrane permeability and content leakage, and destruction of organelle membranes such as coarse endoplasmic reticulum and vacuole. Moreover, TPB destroyed the function of adenine nucleotide transferase (ANT), leading to ATP transport obstruction in mitochondria, inhibiting mPTP opening, inducing intracellular ROS accumulation and mitochondrial membrane potential loss, finally resulting in mitochondrial damage including mitochondria swelled, mitochondrial membrane dissolved, and cristae destroyed and reduced. RNA-seq analyses showed that TPB increased the expression of ERG11, ERG24, ERG6, ERG5, ERG3 and ERG2 genes in ergosterol synthesis pathway, interfered with the expression of genes (NDUFS5, ATPeV0E, NCA2 and Pam17) related to mitochondrial structure, and inhibited the expression of genes (WrbA and GST) related to anti-oxidative stress. CONCLUSIONS TPB exhibited excellent antifungal activity against Ggt by inhibiting ergosterol synthesis and destroying ANT function. So, TPB was a novel compound with dual-target mechanism of action and can be considered a promising novel fungicide for the control of wheat Take-all. The results provided new guides for the structural design of active compounds and powerful tools for pathogen resistance management. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Limin Wang
- High & New Technology Research Center of Henan Academy of Sciences, Zhengzhou, People's Republic of China
| | - Xiaoyu Song
- High & New Technology Research Center of Henan Academy of Sciences, Zhengzhou, People's Republic of China
| | - Yi-Nan Cheng
- Plant Protection College of Henan Agricultural University, Zhengzhou, People's Republic of China
- Engineering Research Center for Plant Health Protection Technology in Henan Province, Zhengzhou, People's Republic of China
| | - Senxiang Cheng
- High & New Technology Research Center of Henan Academy of Sciences, Zhengzhou, People's Republic of China
| | - Tong Chen
- High & New Technology Research Center of Henan Academy of Sciences, Zhengzhou, People's Republic of China
| | - Honglian Li
- Plant Protection College of Henan Agricultural University, Zhengzhou, People's Republic of China
- Engineering Research Center for Plant Health Protection Technology in Henan Province, Zhengzhou, People's Republic of China
| | - Jingming Yan
- Plant Protection College of Henan Agricultural University, Zhengzhou, People's Republic of China
| | - Xiafei Wang
- Plant Protection College of Henan Agricultural University, Zhengzhou, People's Republic of China
| | - Haifeng Zhou
- Plant Protection College of Henan Agricultural University, Zhengzhou, People's Republic of China
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Wang J, Shen J, Chen D, Liao B, Chen X, Zong Y, Wei Y, Shi Y, Liu Y, Gou L, Zhou X, Cheng L, Ren B. Secretory IgA reduced the ergosterol contents of Candida albicans to repress its hyphal growth and virulence. Appl Microbiol Biotechnol 2024; 108:244. [PMID: 38421461 PMCID: PMC10904422 DOI: 10.1007/s00253-024-13063-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Revised: 01/31/2024] [Accepted: 02/08/2024] [Indexed: 03/02/2024]
Abstract
Candida albicans, one of the most prevalent conditional pathogenic fungi, can cause local superficial infections and lethal systemic infections, especially in the immunocompromised population. Secretory immunoglobulin A (sIgA) is an important immune protein regulating the pathogenicity of C. albicans. However, the actions and mechanisms that sIgA exerts directly against C. albicans are still unclear. Here, we investigated that sIgA directs against C. albicans hyphal growth and virulence to oral epithelial cells. Our results indicated that sIgA significantly inhibited C. albicans hyphal growth, adhesion, and damage to oral epithelial cells compared with IgG. According to the transcriptome and RT-PCR analysis, sIgA significantly affected the ergosterol biosynthesis pathway. Furthermore, sIgA significantly reduced the ergosterol levels, while the addition of exogenous ergosterol restored C. albicans hyphal growth and adhesion to oral epithelial cells, indicating that sIgA suppressed the growth of hyphae and the pathogenicity of C. albicans by reducing its ergosterol levels. By employing the key genes mutants (erg11Δ/Δ, erg3Δ/Δ, and erg3Δ/Δ erg11Δ/Δ) from the ergosterol pathway, sIgA lost the hyphal inhibition on these mutants, while sIgA also reduced the inhibitory effects of erg11Δ/Δ and erg3Δ/Δ and lost the inhibition of erg3Δ/Δ erg11Δ/Δ on the adhesion to oral epithelial cells, further proving the hyphal repression of sIgA through the ergosterol pathway. We demonstrated for the first time that sIgA inhibited C. albicans hyphal development and virulence by affecting ergosterol biosynthesis and suggest that ergosterol is a crucial regulator of C. albicans-host cell interactions. KEY POINTS: • sIgA repressed C. albicans hyphal growth • sIgA inhibited C. albicans virulence to host cells • sIgA affected C. albicans hyphae and virulence by reducing its ergosterol levels.
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Affiliation(s)
- Jiannan Wang
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Jiawei Shen
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Ding Chen
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Binyou Liao
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Xi Chen
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Yawen Zong
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Yu Wei
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Yangyang Shi
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Yaqi Liu
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
- Department of Pediatric Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Lichen Gou
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Xuedong Zhou
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Lei Cheng
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China.
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China.
| | - Biao Ren
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China.
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Zhou H, Yang N, Li W, Peng X, Dong J, Jiang Y, Yan L, Zhang D, Jin Y. Exploration of Baicalein-Core Derivatives as Potent Antifungal Agents: SAR and Mechanism Insights. Molecules 2023; 28:6340. [PMID: 37687172 PMCID: PMC10489750 DOI: 10.3390/molecules28176340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 08/23/2023] [Accepted: 08/28/2023] [Indexed: 09/10/2023] Open
Abstract
Baicalein (BE), the major component of Scutellaria Baicalensis, exhibited potently antifungal activity against drug-resistant Candida albicans, and strong inhibition on biofilm formation. Therefore, a series of baicalein-core derivatives were designed and synthesized to find more potent compounds and investigate structure-activity relationship (SAR) and mode of action (MoA). Results demonstrate that A4 and B5 exert a more potent antifungal effect (MIC80 = 0.125 μg/mL) than BE (MIC80 = 4 μg/mL) when used in combination with fluconazole (FLC), while the MIC80 of FLC dropped from 128 μg/mL to 1 μg/mL. SAR analysis indicates that the presence of 5-OH is crucial for synergistic antifungal activities, while o-dihydroxyls and vic-trihydroxyls are an essential pharmacophore, whether they are located on the A ring or the B ring of flavonoids. The MoA demonstrated that these compounds exhibited potent antifungal effects by inhibiting hypha formation of C. albicans. However, sterol composition assay and enzymatic assay conducted in vitro indicated minimal impact of these compounds on sterol biosynthesis and Eno1. These findings were further confirmed by the results of the in-silico assay, which assessed the stability of the complexes. Moreover, the inhibition of hypha of this kind of compound could be attributed to their effect on the catalytic subunit of 1,3-β-d-glucan synthase, 1,3-β-d-glucan-UDP glucosyltransferase and glycosyl-phosphatidylinositol protein, rather than inhibiting ergosterol biosynthesis and Eno1 activity by Induced-Fit Docking and Molecular Dynamics Simulations. This study presents potential antifungal agents with synergistic effects that can effectively inhibit hypha formation. It also provides new insights into the MoA.
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Affiliation(s)
- Heyang Zhou
- School of Pharmacy, Naval Medical University, Shanghai 200433, China; (H.Z.); (L.Y.)
| | - Niao Yang
- School of Pharmacy, Naval Medical University, Shanghai 200433, China; (H.Z.); (L.Y.)
| | - Wei Li
- School of Pharmacy, Naval Medical University, Shanghai 200433, China; (H.Z.); (L.Y.)
| | - Xuemi Peng
- School of Pharmacy, Naval Medical University, Shanghai 200433, China; (H.Z.); (L.Y.)
| | - Jiaxiao Dong
- School of Pharmacy, Anhui Medical University, Hefei 230022, China
| | - Yuanying Jiang
- Department of Pharmacy, Shanghai Tenth People’s Hospital, School of Medicine, Tongji University, Shanghai 200072, China;
| | - Lan Yan
- School of Pharmacy, Naval Medical University, Shanghai 200433, China; (H.Z.); (L.Y.)
| | - Dazhi Zhang
- School of Pharmacy, Naval Medical University, Shanghai 200433, China; (H.Z.); (L.Y.)
| | - Yongsheng Jin
- School of Pharmacy, Naval Medical University, Shanghai 200433, China; (H.Z.); (L.Y.)
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Remines M, Schoonover M, Knox Z, Kenwright K, Hoffert KM, Coric A, Mead J, Ampfer J, Seye S, Strome ED. Profiling The Compendium Of Changes In Saccharomyces cerevisiae Due To Mutations That Alter Availability Of The Main Methyl Donor S-Adenosylmethionine. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.09.544294. [PMID: 37333147 PMCID: PMC10274911 DOI: 10.1101/2023.06.09.544294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
The SAM1 and SAM2 genes encode for S-AdenosylMethionine (AdoMet) synthetase enzymes, with AdoMet serving as the main methyl donor. We have previously shown that independent deletion of these genes alters chromosome stability and AdoMet concentrations in opposite ways in S. cerevisiae. To characterize other changes occurring in these mutants, we grew wildtype, sam1∆/sam1∆, and sam2∆/sam2∆ strains in 15 different Phenotypic Microarray plates with different components, equal to 1440 wells, and measured for growth variations. RNA-Sequencing was also carried out on these strains and differential gene expression determined for each mutant. In this study, we explore how the phenotypic growth differences are linked to the altered gene expression, and thereby predict the mechanisms by which loss of the SAM genes and subsequent AdoMet level changes, impact S. cerevisiae pathways and processes. We present six stories, discussing changes in sensitivity or resistance to azoles, cisplatin, oxidative stress, arginine biosynthesis perturbations, DNA synthesis inhibitors, and tamoxifen, to demonstrate the power of this novel methodology to broadly profile changes due to gene mutations. The large number of conditions that result in altered growth, as well as the large number of differentially expressed genes with wide-ranging functionality, speaks to the broad array of impacts that altering methyl donor abundance can impart, even when the conditions tested were not specifically selected as targeting known methyl involving pathways. Our findings demonstrate that some cellular changes are directly related to AdoMet-dependent methyltransferases and AdoMet availability, some are directly linked to the methyl cycle and its role is production of several important cellular components, and others reveal impacts of SAM gene mutations on previously unconnected pathways.
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Affiliation(s)
- McKayla Remines
- Department of Biological Sciences, Northern Kentucky University, Highland Heights, KY 41099
| | - Makailyn Schoonover
- Department of Biological Sciences, Northern Kentucky University, Highland Heights, KY 41099
| | - Zoey Knox
- Department of Biological Sciences, Northern Kentucky University, Highland Heights, KY 41099
| | - Kailee Kenwright
- Department of Biological Sciences, Northern Kentucky University, Highland Heights, KY 41099
| | - Kellyn M. Hoffert
- Department of Biological Sciences, Northern Kentucky University, Highland Heights, KY 41099
| | - Amila Coric
- Department of Biological Sciences, Northern Kentucky University, Highland Heights, KY 41099
| | - James Mead
- Department of Biological Sciences, Northern Kentucky University, Highland Heights, KY 41099
| | - Joseph Ampfer
- Department of Biological Sciences, Northern Kentucky University, Highland Heights, KY 41099
| | - Serigne Seye
- Department of Biological Sciences, Northern Kentucky University, Highland Heights, KY 41099
| | - Erin D. Strome
- Department of Biological Sciences, Northern Kentucky University, Highland Heights, KY 41099
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Ma J, Xu C, Jiang N, Meng Y, Zhou Y, Xue M, Liu W, Li Y, Fan Y. Transcriptomics in Rare Minnow ( Gobiocypris rarus) towards Attenuated and Virulent Grass Carp Reovirus Genotype II Infection. Animals (Basel) 2023; 13:1870. [PMID: 37889762 PMCID: PMC10251909 DOI: 10.3390/ani13111870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 05/31/2023] [Accepted: 06/02/2023] [Indexed: 10/29/2023] Open
Abstract
Grass carp reovirus genotype Ⅱ (GCRV Ⅱ) causes a variety of fish hemorrhagic disease, which seriously affects the sustainable development of grass carp aquaculture in China. Rare minnow (Gobiocypris rarus) is an ideal model fish to study the pathogenesis of GCRV Ⅱ. To investigate the involved molecular responses against the GCRV Ⅱ infection, we performed comparative transcriptomic analysis in the spleen and liver of rare minnow injected with virulent strain DY197 and attenuated strain QJ205. Results showed that the virulent DY197 strain induced more differently expressed genes (DEGs) than the attenuated QJ205 strain, and tissue-specific responses were induced. In the spleen, the attenuated and virulent strains induced different DEGs; the attenuated QJ205 infection activated steroid synthesis pathway that involved in membrane formation; however, virulent DY197 infection activated innate immunity and apoptosis related pathways while suppressing cell proliferation and migration related pathways that are important for damage tissue repair, as well as hemorrhage related pathways. In the liver, the attenuated and virulent strains infection induced similar DEGs; both strains infection activated immunity and apoptosis related pathways but suppressed metabolism-related pathways; virulent DY197 infection especially activated protein digestion and absorption-related pathways and suppressed steroid synthesis pathway. To conclude, virulent strain infection especially induced tissue-specific alterations and caused severe suppression of hemorrhage-related pathways in spleen. Our findings will contribute to better understanding of the interactions between host and GCRV II.
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Affiliation(s)
- Jie Ma
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China; (J.M.); (C.X.); (N.J.); (Y.M.); (Y.Z.); (M.X.); (W.L.); (Y.L.)
- National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China
| | - Chen Xu
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China; (J.M.); (C.X.); (N.J.); (Y.M.); (Y.Z.); (M.X.); (W.L.); (Y.L.)
| | - Nan Jiang
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China; (J.M.); (C.X.); (N.J.); (Y.M.); (Y.Z.); (M.X.); (W.L.); (Y.L.)
| | - Yan Meng
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China; (J.M.); (C.X.); (N.J.); (Y.M.); (Y.Z.); (M.X.); (W.L.); (Y.L.)
| | - Yong Zhou
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China; (J.M.); (C.X.); (N.J.); (Y.M.); (Y.Z.); (M.X.); (W.L.); (Y.L.)
| | - Mingyang Xue
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China; (J.M.); (C.X.); (N.J.); (Y.M.); (Y.Z.); (M.X.); (W.L.); (Y.L.)
| | - Wenzhi Liu
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China; (J.M.); (C.X.); (N.J.); (Y.M.); (Y.Z.); (M.X.); (W.L.); (Y.L.)
| | - Yiqun Li
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China; (J.M.); (C.X.); (N.J.); (Y.M.); (Y.Z.); (M.X.); (W.L.); (Y.L.)
| | - Yuding Fan
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China; (J.M.); (C.X.); (N.J.); (Y.M.); (Y.Z.); (M.X.); (W.L.); (Y.L.)
- National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China
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9
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Han S, Sheng B, Zhu D, Chen J, Cai H, Zhang S, Guo C. Role of FoERG3 in Ergosterol Biosynthesis by Fusarium oxysporum and the Associated Regulation by Bacillus subtilis HSY21. PLANT DISEASE 2023:PDIS05221010RE. [PMID: 36320138 DOI: 10.1094/pdis-05-22-1010-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Ergosterol is an important component of the fungal cell membrane and represents an effective target of chemical pesticides. However, the current understanding of ergosterol biosynthesis in the soybean root rot pathogen Fusarium oxysporum remains limited. In addition, the regular use of fungicides that inhibit ergosterol synthesis will seriously harm the ecological environment and human health. Bacillus subtilis is gradually replacing chemical control as a safe and effective biological agent; to investigate its effect on ergosterol synthesis of F. oxysporum, we verified the biological function of the FoERG3 gene of F. oxysporum by constructing knockout mutants. The results showed that knocking out FoERG3 blocked ergosterol biosynthesis, restricted mycelial growth, and increased the sensitivity to external stressors (NaCl, D-sorbitol, Congo Red, and H2O2). The increased permeability of the cell membrane promoted increased extracellular K+ levels and decreased mitochondrial cytochrome C contents. Treatment with suspension of B. subtilis HSY21 cells resulted in similar damage as observed when treating FoERG3-knockout F. oxysporum cells with ergosterol, which was characterised by deformity and swelling of the mycelium surface; increased membrane permeability; decreased pathogenicity to soybeans; and significantly decreased activities of cellulase, β-glucosidase, amylase, and pectin-methyl galactosylase. Notably, deleting FoERG3 resulted in a significant lag in the defense-response time of soybeans. Our results suggest that FoERG3 strongly influences the virulence of F. oxysporum and may be used as a potential antimicrobial target by B. subtilis HSY21 to inhibit ergosterol synthesis, which supports the use of B. subtilis as a biological control agent for protecting against F. oxysporum infection.
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Affiliation(s)
- Songyang Han
- Key Laboratory of Molecular Cytogenetics and Genetic Breeding of Heilongjiang Province, College of Life Science and Technology, Harbin Normal University, Harbin 150030, China
| | - Boxiang Sheng
- Key Laboratory of Molecular Cytogenetics and Genetic Breeding of Heilongjiang Province, College of Life Science and Technology, Harbin Normal University, Harbin 150030, China
| | - Dan Zhu
- Key Laboratory of Molecular Cytogenetics and Genetic Breeding of Heilongjiang Province, College of Life Science and Technology, Harbin Normal University, Harbin 150030, China
| | - Jiaxin Chen
- Key Laboratory of Molecular Cytogenetics and Genetic Breeding of Heilongjiang Province, College of Life Science and Technology, Harbin Normal University, Harbin 150030, China
| | - Hongsheng Cai
- Key Laboratory of Molecular Cytogenetics and Genetic Breeding of Heilongjiang Province, College of Life Science and Technology, Harbin Normal University, Harbin 150030, China
| | - Shuzhen Zhang
- Soybean Research Institute of Northeast Agricultural University, Key Laboratory of Soybean Biology of Chinese Education Ministry, Harbin 150030, China
| | - Changhong Guo
- Key Laboratory of Molecular Cytogenetics and Genetic Breeding of Heilongjiang Province, College of Life Science and Technology, Harbin Normal University, Harbin 150030, China
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10
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The Antidepressant Sertraline Affects Cell Signaling and Metabolism in Trichophyton rubrum. J Fungi (Basel) 2023; 9:jof9020275. [PMID: 36836389 PMCID: PMC9961077 DOI: 10.3390/jof9020275] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 01/24/2023] [Accepted: 02/08/2023] [Indexed: 02/22/2023] Open
Abstract
The dermatophyte Trichophyton rubrum is responsible for most human cutaneous infections. Its treatment is complex, mainly because there are only a few structural classes of fungal inhibitors. Therefore, new strategies addressing these problems are essential. The development of new drugs is time-consuming and expensive. The repositioning of drugs already used in medical practice has emerged as an alternative to discovering new drugs. The antidepressant sertraline (SRT) kills several important fungal pathogens. Accordingly, we investigated the inhibitory mechanism of SRT in T. rubrum to broaden the knowledge of its impact on eukaryotic microorganisms and to assess its potential for future use in dermatophytosis treatments. We performed next-generation sequencing (RNA-seq) to identify the genes responding to SRT at the transcript level. We identified that a major effect of SRT was to alter expression for genes involved in maintaining fungal cell wall and plasma membrane stability, including ergosterol biosynthetic genes. SRT also altered the expression of genes encoding enzymes related to fungal energy metabolism, cellular detoxification, and defense against oxidative stress. Our findings provide insights into a specific molecular network interaction that maintains metabolic stability and is perturbed by SRT, showing potential targets for its strategic use in dermatophytosis.
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11
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Wang W, Nie Y, Liu XY, Huang B. The genome and transcriptome of Sarocladium terricola provide insight into ergosterol biosynthesis. Front Cell Infect Microbiol 2023; 13:1181287. [PMID: 37124038 PMCID: PMC10140317 DOI: 10.3389/fcimb.2023.1181287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 03/28/2023] [Indexed: 05/02/2023] Open
Abstract
Sarocladium terricola is a species of ascomycete fungus that has been recognized as a biocontrol agent for managing animal and plant pathogens, and exhibits significant potential as a feed additive. In this study, we utilized a combination of short-read Illumina sequencing and long-read PacBio sequencing to sequence, assemble, and analyze the genome of S. terricola. The resulting genome consisted of 11 scaffolds encompassing 30.27 Mb, with a GC content of 54.07%, and 10,326 predicted protein coding gene models. We utilized 268 single-copy ortholog genes to reconstruct the phylogenomic relationships among 26 ascomycetes, and found that S. terricola was closely related to two Acremonium species. We also determined that the ergosterol content of S. terricola was synthesized to nearly double levels when cultured in potato dextrose media compared to bean media (4509 mg/kg vs. 2382 mg/kg). Furthermore, transcriptome analyses of differentially expressed genes suggested that the ergosterol synthesis genes ERG3, ERG5, and ERG25 were significantly up-regulated in potato dextrose media. These results will help us to recognize metabolic pathway of ergosterol biosynthesis of S. terricloa comprehensivelly.
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Affiliation(s)
- Wei Wang
- Anhui Provincial Key Laboratory for Microbial Pest Control, Anhui Agricultural University, Hefei, China
| | - Yong Nie
- Anhui Provincial Key Laboratory for Microbial Pest Control, Anhui Agricultural University, Hefei, China
| | - Xiao-Yong Liu
- College of Life Sciences, Shandong Normal University, Jinan, China
| | - Bo Huang
- Anhui Provincial Key Laboratory for Microbial Pest Control, Anhui Agricultural University, Hefei, China
- *Correspondence: Bo Huang,
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12
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Anthonies S, Vargas-Muñiz JM. Hortaea werneckii isolates exhibit different pathogenic potential in the invertebrate infection model Galleria mellonella. FRONTIERS IN FUNGAL BIOLOGY 2022; 3:941691. [PMID: 37746169 PMCID: PMC10512279 DOI: 10.3389/ffunb.2022.941691] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 11/07/2022] [Indexed: 09/26/2023]
Abstract
Hortaea werneckii is a black yeast with a remarkable tolerance to salt. Most studies have been dedicated to understanding how H. werneckii adapts to hypersaline environments. H. werneckii has an unconventional cell cycle in which it alternates between fission and budding, which is modulated by cell density. Additionally, H. werneckii can cause superficial mycosis of the palm and sole of humans. Here, we determine the impact of salt concentration on the EXF-2000 strain's cell division pattern and morphology by performing timelapse microscopy at different salt concentrations. At low density and no salt, EXF-2000 primarily grows as pseudohyphae dividing mainly by septation. When grown in the presence of salt at a similar concentration to saltwater or hypersaline environments, we observe it grows first by undergoing fission followed by budding at the poles. Then, we examined a collection of 16 isolates in the presence of 0.6M NaCl, including isolates from marine and hypersaline environments and isolates from patients. These isolates exhibit a wide diversity in colony shape and cellular morphology. The isolates grew as yeast, pseudohyphae, and true hyphae, indicating that isolates can exhibit various cell morphologies under similar environmental conditions. We used the insect larvae Galleria mellonella to determine the pathogenic potential of our isolates. We observe that only a subset of isolates can cause death in our model, and there was no correlation between H. werneckii morphology and capacity to cause disease. Taken together, H. werneckii genomic and phenotypic diversity can serve as a model to better understand how phenotypes and pathogenic potential evolve in environmental fungi.
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Affiliation(s)
- Stephanie Anthonies
- Biological Sciences Program, School of Biological Sciences, Southern Illinois University, Carbondale, IL, United States
| | - José M. Vargas-Muñiz
- Microbiology Program, School of Biological Science, Southern Illinois University, Carbondale, IL, United States
- Whitman Center, Marine Biological Laboratory, Woods Hole, MA, United States
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13
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Gaspar-Cordeiro A, Amaral C, Pobre V, Antunes W, Petronilho A, Paixão P, Matos AP, Pimentel C. Copper Acts Synergistically With Fluconazole in Candida glabrata by Compromising Drug Efflux, Sterol Metabolism, and Zinc Homeostasis. Front Microbiol 2022; 13:920574. [PMID: 35774458 PMCID: PMC9237516 DOI: 10.3389/fmicb.2022.920574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 05/23/2022] [Indexed: 11/18/2022] Open
Abstract
The synergistic combinations of drugs are promising strategies to boost the effectiveness of current antifungals and thus prevent the emergence of resistance. In this work, we show that copper and the antifungal fluconazole act synergistically against Candida glabrata, an opportunistic pathogenic yeast intrinsically tolerant to fluconazole. Analyses of the transcriptomic profile of C. glabrata after the combination of copper and fluconazole showed that the expression of the multidrug transporter gene CDR1 was decreased, suggesting that fluconazole efflux could be affected. In agreement, we observed that copper inhibits the transactivation of Pdr1, the transcription regulator of multidrug transporters and leads to the intracellular accumulation of fluconazole. Copper also decreases the transcriptional induction of ergosterol biosynthesis (ERG) genes by fluconazole, which culminates in the accumulation of toxic sterols. Co-treatment of cells with copper and fluconazole should affect the function of proteins located in the plasma membrane, as several ultrastructural alterations, including irregular cell wall and plasma membrane and loss of cell wall integrity, were observed. Finally, we show that the combination of copper and fluconazole downregulates the expression of the gene encoding the zinc-responsive transcription regulator Zap1, which possibly, together with the membrane transporters malfunction, generates zinc depletion. Supplementation with zinc reverts the toxic effect of combining copper with fluconazole, underscoring the importance of this metal in the observed synergistic effect. Overall, this work, while unveiling the molecular basis that supports the use of copper to enhance the effectiveness of fluconazole, paves the way for the development of new metal-based antifungal strategies.
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Affiliation(s)
- Ana Gaspar-Cordeiro
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Catarina Amaral
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Vânia Pobre
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Wilson Antunes
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
- Centro de Investigação da Academia Militar (CINAMIL), Unidade Militar Laboratorial de Defesa Biológica e Química (UMLDBQ), Lisbon, Portugal
| | - Ana Petronilho
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Paulo Paixão
- Unidade de Infeção, Faculdade de Ciências Médicas, Chronic Diseases Research Centre – CEDOC, NOVA Medical School, Universidade NOVA de Lisboa, Lisbon, Portugal
- Laboratório de Patologia Clínica – SYNLAB, Hospital da Luz, Lisbon, Portugal
| | - António P. Matos
- Egas Moniz Interdisciplinary Research Centre, Egas Moniz Higher Education Cooperative, Caparica, Portugal
| | - Catarina Pimentel
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
- *Correspondence: Catarina Pimentel,
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14
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Titration of C-5 Sterol Desaturase Activity Reveals Its Relationship to Candida albicans Virulence and Antifungal Susceptibility Is Dependent upon Host Immune Status. mBio 2022; 13:e0011522. [PMID: 35380453 PMCID: PMC9040724 DOI: 10.1128/mbio.00115-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The azole antifungals inhibit sterol 14α-demethylase (S14DM), which depletes cellular ergosterol and promotes synthesis of the dysfunctional lipid 14α-methylergosta-8,24(28)-dien-3β,6α-diol, ultimately arresting growth. Mutations that inactivate sterol Δ5,6-desaturase (Erg3p), the enzyme that produces the sterol-diol upon S14DM inhibition, enhances Candida albicans growth in the presence of the azoles. However, erg3 null mutants are sensitive to some physiological stresses and can be less virulent than the wild type. These fitness defects may disfavor the selection of null mutants within patients. The objective of this study was to investigate the relationship between Erg3p activity, C. albicans pathogenicity, and the efficacy of azole therapy. An isogenic panel of strains was constructed that produce various levels of the ERG3 transcript. Analysis of the sterol composition confirmed a correspondingly wide range of Erg3p activity. Phenotypic analysis revealed that even moderate reductions in Erg3p activity are sufficient to greatly enhance C. albicans growth in the presence of fluconazole in vitro without impacting fitness. Moreover, even low levels of Erg3p activity are sufficient to support full virulence of C. albicans in the mouse model of disseminated infection. Finally, while the antifungal efficacy of fluconazole was similar for all strains in immunocompetent mice, there was an inverse correlation between Erg3p activity and the capacity of C. albicans to endure treatment in leukopenic mice. Collectively, these results establish that relative levels of Erg3p activity determine the antifungal efficacy of the azoles upon C. albicans and reveal the critical importance of host immunity in determining the clinical impact of this resistance mechanism. IMPORTANCE Mutations that completely inactivate Erg3p enable the prevalent human pathogen C. albicans to endure the azole antifungals in vitro. However, such null mutants are less frequently identified in azole-resistant clinical isolates than other resistance mechanisms, and previous studies have reported conflicting outcomes regarding antifungal resistance of these mutants in animal models of infection. The results of this study clearly establish a direct correlation between the level of Erg3p activity and the antifungal efficacy of fluconazole within a susceptible mammalian host. In addition, low levels of Erg3p activity are apparently more advantageous for C. albicans survival of azole therapy than complete loss of function. These findings suggest a more nuanced but more important role for Erg3p as a determinant of the clinical efficacy of the azole antifungals than previously appreciated. A revised model of the relationship between Erg3p activity, host immunity, and the antifungal susceptibility of C. albicans is proposed.
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15
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K143R Amino Acid Substitution in 14-α-Demethylase (Erg11p) Changes Plasma Membrane and Cell Wall Structure of Candida albicans. Int J Mol Sci 2022; 23:ijms23031631. [PMID: 35163552 PMCID: PMC8836035 DOI: 10.3390/ijms23031631] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/27/2022] [Accepted: 01/28/2022] [Indexed: 02/07/2023] Open
Abstract
The opportunistic pathogen Candida albicans is responsible for life-threating infections in immunocompromised individuals. Azoles and polyenes are two of the most commonly used antifungals and target the ergosterol biosynthesis pathway or ergosterol itself. A limited number of clinically employed antifungals correspond to the development of resistance mechanisms. One resistance mechanism observed in clinical isolates of azole-resistant C. albicans is the introduction of point mutations in the ERG11 gene, which encodes a key enzyme (lanosterol 14-α-demethylase) on the ergosterol biosynthesis pathway. Here, we demonstrate that a point mutation K143R in ERG11 (C. albicans ERG11K143R/K143R) contributes not only to azole resistance, but causes increased gene expression. Overexpression of ERG11 results in increased ergosterol content and a significant reduction in plasma membrane fluidity. Simultaneously, the same point mutation caused cell wall remodeling. This could be facilitated by the unmasking of chitin and β-glucan on the fungal cell surface, which can lead to recognition of the highly immunogenic β-glucan, triggering a stronger immunological reaction. For the first time, we report that a frequently occurring azole-resistance strategy makes C. albicans less susceptible to azole treatment while, at the same time, affects its cell wall architecture, potentially leading to exposure of the pathogen to a more effective host immune response.
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16
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Li H, Cai Y, Deng Q, Bao H, Chen J, Shen W. Cytochrome P450 Sterol 14 Alpha-Demethylase Gene SsCI72380 Is Required for Mating/Filamentation and Pathogenicity in Sporisorium scitamineum. Front Microbiol 2022; 12:696117. [PMID: 35002988 PMCID: PMC8733404 DOI: 10.3389/fmicb.2021.696117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 12/01/2021] [Indexed: 11/13/2022] Open
Abstract
Sugarcane smut is a significant sugarcane disease caused by Sporisorium scitamineum and is a large threat to the sugar industry in China and the world. Accordingly, it is important to study the pathogenic mechanism by which this disease occurs to identify effective prevention and control strategies. Gene SsCI72380, which encodes cytochrome P450 sterol 14 alpha-demethylase (CYP51), was screened out from the transcriptome of S. scitamineum. In this study, the functions of gene SsCI72380 were identified via the knockout mutants ΔSs72380+ and ΔSs72380−, which were obtained by polyethylene glycol (PEG)-mediated protoplast transformation technology, as well as the complementary mutants COM72380+ and COM72380−. The results showed that the CYP51 gene SsCI72380 played an important role in sporidial growth, sexual mating/filamentation, hyphae growth, and pathogenicity in S. scitamineum. Gene SsCI72380 may regulate the biosynthesis process of ergosterol by encoding CYP51 enzymes and then affecting the structure and function of the cell membrane. Gene SsCI72380 also played an important role in the response toward different abiotic stresses, including hyperosmotic stress, oxidative stress, and cell wall stress, by regulating the permeability of the cell membrane. In addition, gene SsCI72380 is a new type of pathogenic gene from S. scitamineum that enhances the pathogenicity of S. scitamineum.
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Affiliation(s)
- Huizhong Li
- College of Agriculture, South China Agricultural University, Guangzhou, China.,Sugarcane Research Laboratory, South China Agricultural University, Guangzhou, China
| | - Yichang Cai
- College of Agriculture, South China Agricultural University, Guangzhou, China.,Sugarcane Research Laboratory, South China Agricultural University, Guangzhou, China
| | - Quanqing Deng
- College of Agriculture, South China Agricultural University, Guangzhou, China.,Sugarcane Research Laboratory, South China Agricultural University, Guangzhou, China
| | - Han Bao
- College of Agriculture, South China Agricultural University, Guangzhou, China.,Sugarcane Research Laboratory, South China Agricultural University, Guangzhou, China
| | - Jianwen Chen
- College of Agriculture, South China Agricultural University, Guangzhou, China.,Sugarcane Research Laboratory, South China Agricultural University, Guangzhou, China
| | - Wankuan Shen
- College of Agriculture, South China Agricultural University, Guangzhou, China.,Sugarcane Research Laboratory, South China Agricultural University, Guangzhou, China.,Scientific Observing and Experimental Station of Crop Cultivation in South China, Ministry of Agriculture and Rural Areas, Guangzhou, China
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17
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Species-Specific Differences in C-5 Sterol Desaturase Function Influence the Outcome of Azole Antifungal Exposure. Antimicrob Agents Chemother 2021; 65:e0104421. [PMID: 34516249 DOI: 10.1128/aac.01044-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The azole antifungals inhibit sterol 14α-demethylase (S14DM), leading to depletion of cellular ergosterol and the synthesis of an aberrant sterol diol that disrupts membrane function. In Candida albicans, sterol diol production is catalyzed by the C-5 sterol desaturase enzyme encoded by ERG3. Accordingly, mutations that inactivate ERG3 enable the fungus to grow in the presence of the azoles. The purpose of this study was to compare the propensities of C-5 sterol desaturases from different fungal pathogens to produce the toxic diol upon S14DM inhibition and thus contribute to antifungal efficacy. The coding sequences of ERG3 homologs from C. albicans (CaERG3), Candida glabrata (CgERG3), Candida auris (CaurERG3), Cryptococcus neoformans (CnERG3), Aspergillus fumigatus (AfERG3A-C) and Rhizopus delemar (RdERG3A/B) were expressed in a C. albicans erg3Δ/Δ mutant to facilitate comparative analysis. All but one of the Erg3p-like proteins (AfErg3C) at least partially restored C-5 sterol desaturase activity and to corresponding degrees rescued the stress and hyphal growth defects of the C. albicans erg3Δ/Δ mutant, confirming functional equivalence. Each C-5 desaturase enzyme conferred markedly different responses to fluconazole exposure in terms of the MIC and residual growth observed at supra-MICs. Upon fluconazole-mediated inhibition of S14DM, the strains expressing each homolog also produced various levels of 14α-methylergosta-8,24(28)-dien-3β,6α-diol. The RdErg3A and AfErg3A proteins are notable for low levels of sterol diol production and failing to confer appreciable azole sensitivity upon the C. albicans erg3Δ/Δ mutant. These findings suggest that species-specific properties of C-5 sterol desaturase may be an important determinant of intrinsic azole sensitivity.
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18
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Hu Y, Niu Y, Ye X, Zhu C, Tong T, Zhou Y, Zhou X, Cheng L, Ren B. Staphylococcus aureus Synergized with Candida albicans to Increase the Pathogenesis and Drug Resistance in Cutaneous Abscess and Peritonitis Murine Models. Pathogens 2021; 10:pathogens10081036. [PMID: 34451500 PMCID: PMC8398722 DOI: 10.3390/pathogens10081036] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 08/05/2021] [Accepted: 08/12/2021] [Indexed: 01/21/2023] Open
Abstract
The mixed species of Staphylococcus aureus and Candida albicans can cause infections on skin, mucosa or bloodstream; however, mechanisms of their cross-kingdom interactions related to pathogenesis and drug resistance are still not clear. Here an increase of S. aureus proliferation and biofilm formation was observed in S. aureus and C. albicans dual-species culture, and the synergistic pathogenic effect was then confirmed in both local (cutaneous abscess) and systemic infection (peritonitis) murine models. According to the transcriptome analysis of the dual-species culture, virulence factors of S. aureus were significantly upregulated. Surprisingly, the beta-lactams and vancomycin-resistant genes in S. aureus as well as azole-resistant genes in C. albicans were also significantly increased. The synergistic effects on drug resistance to both antibacterial and antifungal agents were further proved both in vitro and in cutaneous abscess and peritonitis murine models treated by methicillin, vancomycin and fluconazole. The synergistic interactions between S. aureus and C. albicans on pathogenesis and drug resistance highlight the importance of targeting the microbial interactions in polyspecies-associated infections.
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Affiliation(s)
- Yao Hu
- State Key Laboratory of Oral Diseases, West China School of Stomatology, National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu 610064, China; (Y.H.); (X.Y.); (C.Z.); (T.T.); (Y.Z.)
| | - Yulong Niu
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610041, China;
| | - Xingchen Ye
- State Key Laboratory of Oral Diseases, West China School of Stomatology, National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu 610064, China; (Y.H.); (X.Y.); (C.Z.); (T.T.); (Y.Z.)
| | - Chengguang Zhu
- State Key Laboratory of Oral Diseases, West China School of Stomatology, National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu 610064, China; (Y.H.); (X.Y.); (C.Z.); (T.T.); (Y.Z.)
| | - Ting Tong
- State Key Laboratory of Oral Diseases, West China School of Stomatology, National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu 610064, China; (Y.H.); (X.Y.); (C.Z.); (T.T.); (Y.Z.)
| | - Yujie Zhou
- State Key Laboratory of Oral Diseases, West China School of Stomatology, National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu 610064, China; (Y.H.); (X.Y.); (C.Z.); (T.T.); (Y.Z.)
| | - Xuedong Zhou
- State Key Laboratory of Oral Diseases, West China School of Stomatology, National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu 610064, China; (Y.H.); (X.Y.); (C.Z.); (T.T.); (Y.Z.)
- Correspondence: (X.Z.); (L.C.); (B.R.)
| | - Lei Cheng
- State Key Laboratory of Oral Diseases, West China School of Stomatology, National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu 610064, China; (Y.H.); (X.Y.); (C.Z.); (T.T.); (Y.Z.)
- Correspondence: (X.Z.); (L.C.); (B.R.)
| | - Biao Ren
- State Key Laboratory of Oral Diseases, West China School of Stomatology, National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu 610064, China; (Y.H.); (X.Y.); (C.Z.); (T.T.); (Y.Z.)
- Correspondence: (X.Z.); (L.C.); (B.R.)
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19
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Phytomedicine from Middle Eastern Countries: An Alternative Remedy to Modern Medicine against Candida spp Infection. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2021; 2021:6694876. [PMID: 34335836 PMCID: PMC8298167 DOI: 10.1155/2021/6694876] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 06/22/2021] [Indexed: 12/26/2022]
Abstract
Candida spp are capable of infecting both normal and immunocompromised individuals. More recently, Candida infections have spread considerably in healthcare settings, especially in intensive care units, where it is the most frequently encountered pathogen. Candida albicans is the commonest species encountered, although infections by non-albicans species have also risen in the past few years. The pathogenicity of Candida is credited to its aptitude to change between yeast and hyphal modes of growth. Candida spp produce biofilms on synthetic materials that protect them and facilitate drug resistance and act as a source for chronic and recurrent infections. Primarily, azoles antifungal agents are utilized to treat Candida infection that targets the ergosterol synthesis pathway in the cell wall. The development of antifungal resistance in Candida species is a major reason for treatment failure, and hence, there is a need to develop newer antifungal molecules and/or modifications of existing antifungals to make them more effective and less toxic. This has led researchers to oversee the plants to discover newer antimicrobials. Middle Eastern countries are well known for their landscape ranging from dry and sandy deserts to snow-capped mountains. However, they comprise enormous plant diversity with over 20,000 different species showing various types of bioactivities, such as anticancer, antidiabetic, and antimicrobial activities. Especially, the antifungal potential of these phytoproducts could be exploited in the clinical setting for therapy. The present review examines some of the promising alternative natural compounds that have been tested and found effective in treating Candida infections in vitro in some Middle Eastern countries.
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Zhu T, Chen X, Li C, Tu J, Liu N, Xu D, Sheng C. Lanosterol 14α-demethylase (CYP51)/histone deacetylase (HDAC) dual inhibitors for treatment of Candida tropicalis and Cryptococcus neoformans infections. Eur J Med Chem 2021; 221:113524. [PMID: 33992927 DOI: 10.1016/j.ejmech.2021.113524] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 04/28/2021] [Accepted: 04/30/2021] [Indexed: 12/19/2022]
Abstract
Invasive fungal infections remain a challenge due to lack of effective antifungal agents and serious drug resistance. Discovery of antifungal agents with novel antifungal mechanism is important and urgent. Previously, we designed the first CYP51/HDAC dual inhibitors with potent activity against resistant Candida albicans infections. To better understand the antifungal spectrum and synergistic mechanism, herein new CYP51/HDAC dual inhibitors were designed which showed potent in vitro and in vivo antifungal activity against C. neoformans and C. tropicalis infections. Antifungal mechanism studies revealed that the CYP51/HDAC dual inhibitors acted by inhibiting various virulence factors of C. tropicalis and C. neoformans and down-regulating resistance-associated genes. This study highlights the potential of CYP51/HDAC dual inhibitors as a promising strategy for the discovery of novel broad-spectrum antifungal agents.
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Affiliation(s)
- Tianbao Zhu
- National & Local Joint Engineering Research Center for High-efficiency Refining and High-quality Utilization of Biomass, School of Pharmacy, 1 Gehu Road, Changzhou University, Changzhou, 213164, China; School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai, 200433, China
| | - Xi Chen
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, 1 Xuefu Avenue, Xi'an, 710127, China
| | - Chenglan Li
- School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai, 200433, China
| | - Jie Tu
- School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai, 200433, China
| | - Na Liu
- School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai, 200433, China.
| | - Defeng Xu
- National & Local Joint Engineering Research Center for High-efficiency Refining and High-quality Utilization of Biomass, School of Pharmacy, 1 Gehu Road, Changzhou University, Changzhou, 213164, China.
| | - Chunquan Sheng
- School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai, 200433, China.
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Sircaik S, Román E, Bapat P, Lee KK, Andes DR, Gow NAR, Nobile CJ, Pla J, Panwar SL. The protein kinase Ire1 impacts pathogenicity of Candida albicans by regulating homeostatic adaptation to endoplasmic reticulum stress. Cell Microbiol 2021; 23:e13307. [PMID: 33403715 PMCID: PMC8044019 DOI: 10.1111/cmi.13307] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 12/19/2020] [Accepted: 12/21/2020] [Indexed: 12/20/2022]
Abstract
The unfolded protein response (UPR), crucial for the maintenance of endoplasmic reticulum (ER) homeostasis, is tied to the regulation of multiple cellular processes in pathogenic fungi. Here, we show that Candida albicans relies on an ER‐resident protein, inositol‐requiring enzyme 1 (Ire1) for sensing ER stress and activating the UPR. Compromised Ire1 function impacts cellular processes that are dependent on functional secretory homeostasis, as inferred from transcriptional profiling. Concordantly, an Ire1‐mutant strain exhibits pleiotropic roles in ER stress response, antifungal tolerance, cell wall regulation and virulence‐related traits. Hac1 is the downstream target of C. albicans Ire1 as it initiates the unconventional splicing of the 19 bp intron from HAC1 mRNA during tunicamycin‐induced ER stress. Ire1 also activates the UPR in response to perturbations in cell wall integrity and cell membrane homeostasis in a manner that does not necessitate the splicing of HAC1 mRNA. Furthermore, the Ire1‐mutant strain is severely defective in hyphal morphogenesis and biofilm formation as well as in establishing a successful infection in vivo. Together, these findings demonstrate that C. albicans Ire1 functions to regulate traits that are essential for virulence and suggest its importance in responding to multiple stresses, thus integrating various stress signals to maintain ER homeostasis.
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Affiliation(s)
- Shabnam Sircaik
- Yeast Molecular Genetics Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Elvira Román
- Departamento de Microbiología y Parasitología-IRYCIS, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain
| | - Priyanka Bapat
- Department of Molecular and Cell Biology, University of California, Merced, California, USA.,Quantitative and System Biology Graduate Program, University of California, Merced, California, USA
| | - Keunsook K Lee
- The Aberdeen Fungal Group, MRC Centre for Medical Mycology, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - David R Andes
- Department of Medicine, Section of Infectious Diseases, University of Wisconsin, Madison, Wisconsin, USA
| | - Neil A R Gow
- The Aberdeen Fungal Group, MRC Centre for Medical Mycology, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK.,Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Clarissa J Nobile
- Department of Molecular and Cell Biology, University of California, Merced, California, USA.,Health Sciences Research Institute, University of California, Merced, California, USA
| | - Jesús Pla
- Departamento de Microbiología y Parasitología-IRYCIS, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain
| | - Sneh Lata Panwar
- Yeast Molecular Genetics Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
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Transcriptome Analyses of Candida albicans Biofilms, Exposed to Arachidonic Acid and Fluconazole, Indicates Potential Drug Targets. G3-GENES GENOMES GENETICS 2020; 10:3099-3108. [PMID: 32631950 PMCID: PMC7466979 DOI: 10.1534/g3.120.401340] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Candida albicans is an opportunistic yeast pathogen within the human microbiota with significant medical importance because of its pathogenic potential. The yeast produces highly resistant biofilms, which are crucial for maintaining infections. Though antifungals are available, their effectiveness is dwindling due to resistance. Alternate options that comprise the combination of existing azoles and polyunsaturated fatty acids, such as arachidonic acid (AA), have been shown to increase azoles susceptibility of C. albicans biofilms; however, the mechanisms are still unknown. Therefore, transcriptome analysis was conducted on biofilms exposed to sub-inhibitory concentrations of AA alone, fluconazole alone, and AA combined with fluconazole to understand the possible mechanism involved with the phenomenon. Protein ANalysis THrough Evolutionary Relationships (PANTHER) analysis from the differentially expressed genes revealed that the combination of AA and fluconazole influences biological processes associated with essential processes including methionine synthesis and those involved in ATP generation, such as AMP biosynthesis, fumarate metabolism and fatty acid oxidation. These observations suggests that the interference of AA with these processes may be a possible mechanisms to induce increased antifungal susceptibility.
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Candida glabrata Transcription Factor Rpn4 Mediates Fluconazole Resistance through Regulation of Ergosterol Biosynthesis and Plasma Membrane Permeability. Antimicrob Agents Chemother 2020; 64:AAC.00554-20. [PMID: 32571817 PMCID: PMC7449212 DOI: 10.1128/aac.00554-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 06/13/2020] [Indexed: 01/05/2023] Open
Abstract
The ability to acquire azole resistance is an emblematic trait of the fungal pathogen Candida glabrata. Understanding the molecular basis of azole resistance in this pathogen is crucial for designing more suitable therapeutic strategies. This study shows that the C. glabrata transcription factor (TF) CgRpn4 is a determinant of azole drug resistance. RNA sequencing during fluconazole exposure revealed that CgRpn4 regulates the expression of 212 genes, activating 80 genes and repressing, likely in an indirect fashion, 132 genes. The ability to acquire azole resistance is an emblematic trait of the fungal pathogen Candida glabrata. Understanding the molecular basis of azole resistance in this pathogen is crucial for designing more suitable therapeutic strategies. This study shows that the C. glabrata transcription factor (TF) CgRpn4 is a determinant of azole drug resistance. RNA sequencing during fluconazole exposure revealed that CgRpn4 regulates the expression of 212 genes, activating 80 genes and repressing, likely in an indirect fashion, 132 genes. Targets comprise several proteasome and ergosterol biosynthesis genes, including ERG1, ERG2, ERG3, and ERG11. The localization of CgRpn4 to the nucleus increases upon fluconazole stress. Consistent with a role in ergosterol and plasma membrane homeostasis, CgRpn4 is required for the maintenance of ergosterol levels upon fluconazole stress, which is associated with a role in the upkeep of cell permeability and decreased intracellular fluconazole accumulation. We provide evidence that CgRpn4 directly regulates ERG11 expression through the TTGCAAA binding motif, reinforcing the relevance of this regulatory network in azole resistance. In summary, CgRpn4 is a new regulator of the ergosterol biosynthesis pathway in C. glabrata, contributing to plasma membrane homeostasis and, thus, decreasing azole drug accumulation.
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Squalene-Tetrahymanol Cyclase Expression Enables Sterol-Independent Growth of Saccharomyces cerevisiae. Appl Environ Microbiol 2020; 86:AEM.00672-20. [PMID: 32561581 PMCID: PMC7440791 DOI: 10.1128/aem.00672-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 06/14/2020] [Indexed: 02/08/2023] Open
Abstract
The laboratory experiments described in this report simulate a proposed horizontal gene transfer event during the evolution of strictly anaerobic fungi. The demonstration that expression of a single heterologous gene sufficed to eliminate anaerobic sterol requirements in the model eukaryote Saccharomyces cerevisiae therefore contributes to our understanding of how sterol-independent eukaryotes evolved in anoxic environments. This report provides a proof of principle for a metabolic engineering strategy to eliminate sterol requirements in yeast strains that are applied in large-scale anaerobic industrial processes. The sterol-independent yeast strains described in this report provide a valuable platform for further studies on the physiological roles and impacts of sterols and sterol surrogates in eukaryotic cells. Biosynthesis of sterols, which are considered essential components of virtually all eukaryotic membranes, requires molecular oxygen. Anaerobic growth of the yeast Saccharomyces cerevisiae therefore strictly depends on sterol supplementation of synthetic growth media. Neocallimastigomycota are a group of strictly anaerobic fungi which, instead of containing sterols, contain the pentacyclic triterpenoid “sterol surrogate” tetrahymanol, which is formed by cyclization of squalene. Here, we demonstrate that expression of the squalene-tetrahymanol cyclase gene TtTHC1 from the ciliate Tetrahymena thermophila enables synthesis of tetrahymanol by S. cerevisiae. Moreover, expression of TtTHC1 enabled exponential growth of anaerobic S. cerevisiae cultures in sterol-free synthetic media. After deletion of the ERG1 gene from a TtTHC1-expressing S. cerevisiae strain, native sterol synthesis was abolished and sustained sterol-free growth was demonstrated under anaerobic as well as aerobic conditions. Anaerobic cultures of TtTHC1-expressing S. cerevisiae on sterol-free medium showed lower specific growth rates and biomass yields than ergosterol-supplemented cultures, while their ethanol yield was higher. This study demonstrated that acquisition of a functional squalene-tetrahymanol cyclase gene offers an immediate growth advantage to S. cerevisiae under anaerobic, sterol-limited conditions and provides the basis for a metabolic engineering strategy to eliminate the oxygen requirements associated with sterol synthesis in yeasts. IMPORTANCE The laboratory experiments described in this report simulate a proposed horizontal gene transfer event during the evolution of strictly anaerobic fungi. The demonstration that expression of a single heterologous gene sufficed to eliminate anaerobic sterol requirements in the model eukaryote Saccharomyces cerevisiae therefore contributes to our understanding of how sterol-independent eukaryotes evolved in anoxic environments. This report provides a proof of principle for a metabolic engineering strategy to eliminate sterol requirements in yeast strains that are applied in large-scale anaerobic industrial processes. The sterol-independent yeast strains described in this report provide a valuable platform for further studies on the physiological roles and impacts of sterols and sterol surrogates in eukaryotic cells.
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Kim SW, Park YK, Joo YJ, Chun YJ, Hwang JY, Baek JH, Kim J. Subunits of the vacuolar H+-ATPase complex, Vma4 and Vma10, are essential for virulence and represent potential drug targets in Candida albicans. Fungal Biol 2019; 123:709-722. [DOI: 10.1016/j.funbio.2019.06.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 05/20/2019] [Accepted: 06/03/2019] [Indexed: 01/26/2023]
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Martins MP, Silva LG, Rossi A, Sanches PR, Souza LDR, Martinez-Rossi NM. Global Analysis of Cell Wall Genes Revealed Putative Virulence Factors in the Dermatophyte Trichophyton rubrum. Front Microbiol 2019; 10:2168. [PMID: 31608026 PMCID: PMC6761320 DOI: 10.3389/fmicb.2019.02168] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 09/04/2019] [Indexed: 12/25/2022] Open
Abstract
The fungal cell wall is a structure in constant contact with the external environment. It confers shape to the cell and protects it from external threats. During host adaptation, the cell wall structure of fungal pathogens is continuously reshaped by the orchestrated action of numerous genes. These genes respond to environmental stresses and challenging growth conditions, influencing the infective potential of the fungus. Here, we aimed to identify cell wall biosynthesis-related genes that putatively encode virulence factors in Trichophyton rubrum. We used RNA-seq to examine the impact of two drugs, namely undecanoic acid, and acriflavine as well as the effects of the carbon source switching from glucose to keratin on T. rubrum cell wall metabolism. By using functional annotation based on Gene Ontology terms, we identified significantly differentially expressed cell wall-related genes in all stress conditions. We also exposed T. rubrum to osmotic and other cell wall stressors and evaluated the susceptibility and gene modulation in response to stress. The changes in the ambient environment caused continuous cell wall remodeling, forcing the fungus to undergo modulatory restructuring. The influence of the external challenges indicated a highly complex response pattern. The genes that were modulated simultaneously in the three stress conditions highlight potential targets for antifungal development.
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Affiliation(s)
- Maíra P Martins
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Larissa G Silva
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Antonio Rossi
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Pablo R Sanches
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Larissa D R Souza
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Nilce M Martinez-Rossi
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
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Meza-Menchaca T, Ramos-Ligonio A, López-Monteon A, Vidal Limón A, Kaluzhskiy LA, V Shkel T, V Strushkevich N, Jiménez-García LF, Agredano Moreno LT, Gallegos-García V, Suárez-Medellín J, Trigos Á. Insights into Ergosterol Peroxide's Trypanocidal Activity. Biomolecules 2019; 9:E484. [PMID: 31547423 PMCID: PMC6770379 DOI: 10.3390/biom9090484] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 08/15/2019] [Accepted: 08/19/2019] [Indexed: 12/20/2022] Open
Abstract
Trypanosoma cruzi, which causes Chagas disease, is a significant health threat in many countries and affects millions of people. Given the magnitude of this disease, a broader understanding of trypanocidal mechanisms is needed to prevent and treat infection. Natural endoperoxides, such as ergosterol peroxide, have been shown to be toxic to parasites without causing harm to human cells or tissues. Although prior studies have demonstrated the trypanocidal activity of ergosterol peroxide, the cellular and molecular mechanisms remain unknown. The results of this study indicate that a free-radical reaction occurs in T. cruzi following ergosterol peroxide exposure, leading to cell death. Using a combination of biochemical, microscopic and in silico experimental approaches, we have identified, for the first time, the cellular and molecular cytotoxic mechanism of an ergosterol peroxide obtained from Pleurotus ostreatus (Jacq) P. Kumm. f. sp. Florida.
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Affiliation(s)
- Thuluz Meza-Menchaca
- Laboratorio de Genómica Humana, Facultad de Medicina, Universidad Veracruzana, Médicos y Odontólogos S/N, Col. Unidad del Bosque, Xalapa C.P. 91010, Veracruz, Mexico.
| | - Angel Ramos-Ligonio
- LADISER, Inmunología y Biología Molecular, Facultad de Ciencias Químicas, Universidad Veracruzana, Orizaba 94340, Veracruz, Mexico.
| | - Aracely López-Monteon
- LADISER, Inmunología y Biología Molecular, Facultad de Ciencias Químicas, Universidad Veracruzana, Orizaba 94340, Veracruz, Mexico.
| | - Abraham Vidal Limón
- Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Carr. Tijuana-Ensenada, Col. Pedregal Playitas, Ensenada C.P. 22860, Baja California, Mexico.
| | - Leonid A Kaluzhskiy
- Institute of Biomedical Chemistry, 10 building 8, Pogodinskaya Street, 119121 Moscow, Russia.
| | - Tatjana V Shkel
- Institute of Bioorganic Chemistry NASB, Kuprevich Street, 220141 Minsk, Belarus.
| | | | - Luis Felipe Jiménez-García
- Laboratorio de Microscopía Electrónica, Facultad de Ciencias, Universidad Nacional Autónoma de México (UNAM), Circuito Exterior, Ciudad Universitaria, México D.F. 04510, Mexico.
| | - Lourdes Teresa Agredano Moreno
- Laboratorio de Nano-Biología Celular, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México (UNAM), Circuito Exterior, Ciudad Universitaria, México D.F. 04510, Mexico.
| | - Verónica Gallegos-García
- Facultad de Enfermería y Nutrición, UASLP, Av. Niño Artillero 130, Zona Universitaria Poniente, San Luis Potosí C.P. 78240, Mexico.
| | - Jorge Suárez-Medellín
- Centro de Investigaciones Cerebrales, Universidad Veracruzana, Xalapa 91190, Mexico.
| | - Ángel Trigos
- Centro de Investigación de Micología Aplicada, Universidad Veracruzana, Xalapa 91010, Veracruz, Mexico.
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Braga SS. Multi-target drugs active against leishmaniasis: A paradigm of drug repurposing. Eur J Med Chem 2019; 183:111660. [PMID: 31514064 DOI: 10.1016/j.ejmech.2019.111660] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 08/27/2019] [Accepted: 08/28/2019] [Indexed: 11/17/2022]
Abstract
This mini-review focuses on leishmanicidal drugs that were sourced from small molecules previously approved for other diseases. The mechanisms of action of these molecules are herein explored, to probe the origins of their inter-species growth inhibitory activities. It is shown how the transversal action of the azoles - fluconazole, posaconazole and itraconazole - in both fungi and Leishmania is due to the occurrence of the same target, lanosterol 14-α-demethylase, in these two groups of species. In turn, the drugs miltefosine and amphotericin B are presented as truly multi-target agents, acting on small molecules, proteins, genes and even organelles. Steps towards future leishmanicidal drug candidates based on the multi-target strategy and on drug repurposing are also briefly presented.
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Affiliation(s)
- Susana Santos Braga
- QOPNA & LAQV/REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal.
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Disruption of Membrane Integrity by the Bacterium-Derived Antifungal Jagaricin. Antimicrob Agents Chemother 2019; 63:AAC.00707-19. [PMID: 31235622 DOI: 10.1128/aac.00707-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 06/14/2019] [Indexed: 01/05/2023] Open
Abstract
Jagaricin is a lipopeptide produced by the bacterial mushroom pathogen Janthinobacterium agaricidamnosum, the causative agent of mushroom soft rot disease. Apart from causing lesions in mushrooms, jagaricin is a potent antifungal active against human-pathogenic fungi. We show that jagaricin acts by impairing membrane integrity, resulting in a rapid flux of ions, including Ca2+, into susceptible target cells. Accordingly, the calcineurin pathway is required for jagaricin tolerance in the fungal pathogen Candida albicans Transcriptional profiling of pathogenic yeasts further revealed that jagaricin triggers cell wall strengthening, general shutdown of membrane potential-driven transport, and the upregulation of lipid transporters, linking cell envelope integrity to jagaricin action and resistance. Whereas jagaricin shows hemolytic effects, it exhibited either no or low plant toxicity at concentrations at which the growth of prevalent phytopathogenic fungi is inhibited. Therefore, jagaricin may have potential for agricultural applications. The action of jagaricin as a membrane-disrupting antifungal is promising but would require modifications for use in humans.
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Vuppala S, Chitumalla RK, Joo BS, Jang J. Structure-based lead optimization to improve the antifungal potency of the tetrahydroimidazo pyridine inhibitors targeted to Candida albicans dihydrofolate reductase and lanosterol 14-alpha-demethylase. Med Chem Res 2019. [DOI: 10.1007/s00044-019-02404-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Muthamil S, Balasubramaniam B, Balamurugan K, Pandian SK. Synergistic Effect of Quinic Acid Derived From Syzygium cumini and Undecanoic Acid Against Candida spp. Biofilm and Virulence. Front Microbiol 2018; 9:2835. [PMID: 30534118 PMCID: PMC6275436 DOI: 10.3389/fmicb.2018.02835] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 11/05/2018] [Indexed: 12/14/2022] Open
Abstract
In recent decades, fungal infections have incredibly increased with Candida genus as the major cause of morbidity and mortality in hospitalized and immunocompromised patients. Most of the Candida species are proficient in biofilm formation on implanted medical devices as well as human tissues. Biofilm related Candida infections are very difficult to treat using common antifungal agents owing to their increased drug resistance. To address these issues, the present study investigated the antibiofilm and antivirulent properties of Syzygium cumini derived quinic acid in combination with known antifungal compound undecanoic acid. Initially, antibiofilm potential of S. cumini leaf extract was assessed and the active principles were identified through gas chromatography and mass spectrometry analysis. Among the compounds identified, quinic acid was one of the major compounds. The interaction between quinic acid and undecanoic acid was found to be synergistic in the Fractional inhibitory concentration index (≤0.5). Results of in vitro assays and gene expression analysis suggested that the synergistic combinations of quinic acid and undecanoic acid significantly inhibited virulence traits of Candida spp. such as the biofilm formation, yeast-to-hyphal transition, extracellular polymeric substances production, filamentation, secreted hydrolases production and ergosterol biosynthesis. In addition, result of in vivo studies using Caenorhabditis elegans demonstrated the non-toxic nature of QA-UDA combination and antivirulence effect against Candida spp. For the first time, synergistic antivirulence ability of quinic acid and undecanoic acid was explored against Candida spp. Thus, results obtained from the present study suggest that combination of phytochemicals might be used an alternate therapeutic strategy for the prevention and treatment of biofilm associated Candida infection.
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Candida albicans gains azole resistance by altering sphingolipid composition. Nat Commun 2018; 9:4495. [PMID: 30374049 PMCID: PMC6206040 DOI: 10.1038/s41467-018-06944-1] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 10/03/2018] [Indexed: 12/31/2022] Open
Abstract
Fungal infections by drug-resistant Candida albicans pose a global public health threat. However, the pathogen’s diploid genome greatly hinders genome-wide investigations of resistance mechanisms. Here, we develop an efficient piggyBac transposon-mediated mutagenesis system using stable haploid C. albicans to conduct genome-wide genetic screens. We find that null mutants in either gene FEN1 or FEN12 (encoding enzymes for the synthesis of very-long-chain fatty acids as precursors of sphingolipids) exhibit resistance to fluconazole, a first-line antifungal drug. Mass-spectrometry analyses demonstrate changes in cellular sphingolipid composition in both mutants, including substantially increased levels of several mannosylinositolphosphoceramides with shorter fatty-acid chains. Treatment with fluconazole induces similar changes in wild-type cells, suggesting a natural response mechanism. Furthermore, the resistance relies on a robust upregulation of sphingolipid biosynthesis genes. Our results shed light into the mechanisms underlying azole resistance, and the new transposon-mediated mutagenesis system should facilitate future genome-wide studies of C. albicans. The fungal pathogen Candida albicans is diploid, which hinders genome-wide studies. Here, Gao et al. present a piggyBac transposon-mediated mutagenesis system using stable haploid C. albicans strains, and use it to identify genes and mechanisms underlying azole resistance.
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Song J, Zhang S, Lu L. Fungal cytochrome P450 protein Cyp51: What we can learn from its evolution, regulons and Cyp51-based azole resistance. FUNGAL BIOL REV 2018. [DOI: 10.1016/j.fbr.2018.05.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Loss of Upc2p-Inducible ERG3 Transcription Is Sufficient To Confer Niche-Specific Azole Resistance without Compromising Candida albicans Pathogenicity. mBio 2018; 9:mBio.00225-18. [PMID: 29789366 PMCID: PMC5964354 DOI: 10.1128/mbio.00225-18] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Inactivation of sterol Δ5,6-desaturase (Erg3p) in the prevalent fungal pathogen Candida albicans is one of several mechanisms that can confer resistance to the azole antifungal drugs. However, loss of Erg3p activity is also associated with deficiencies in stress tolerance, invasive hyphal growth, and attenuated virulence in a mouse model of disseminated infection. This may explain why relatively few erg3-deficient strains have been reported among azole-resistant clinical isolates. In this study, we examined the consequences of Erg3p inactivation upon C. albicans pathogenicity and azole susceptibility in mouse models of mucosal and disseminated infection. While a C. albicanserg3Δ/Δ mutant was unable to cause lethality in the disseminated model, it induced pathology in a mouse model of vaginal infection. The erg3Δ/Δ mutant was also more resistant to fluconazole treatment than the wild type in both models of infection. Thus, complete loss of Erg3p activity confers azole resistance but also niche-specific virulence deficiencies. Serendipitously, we discovered that loss of azole-inducible ERG3 transcription (rather than complete inactivation) is sufficient to confer in vitro fluconazole resistance, without compromising C. albicans stress tolerance, hyphal growth, or pathogenicity in either mouse model. It is also sufficient to confer fluconazole resistance in the mouse vaginal model, but not in the disseminated model of infection, and thus confers niche-specific azole resistance without compromising C. albicans pathogenicity at either site. Collectively, these results establish that modulating Erg3p expression or activity can have niche-specific consequences on both C. albicans pathogenicity and azole resistance. While conferring resistance to the azole antifungals in vitro, loss of sterol Δ5,6-desaturase (Erg3p) activity has also been shown to reduce C. albicans pathogenicity. Accordingly, it has been presumed that this mechanism may not be significant in the clinical setting. The results presented here challenge this assumption, revealing a more complex relationship between Erg3p activity, azole resistance, C. albicans pathogenicity, and the specific site of infection. Most importantly, we have shown that even modest changes in ERG3 transcription are sufficient to confer azole resistance without compromising C. albicans fitness or pathogenicity. Given that previous efforts to assess the importance of ERG3 as a determinant of clinical azole resistance have focused almost exclusively on detecting null mutants, its role may have been grossly underestimated. On the basis of our results, a more thorough investigation of the contribution of the ERG3 gene to azole resistance in the clinical setting is warranted.
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Mioka T, Fujimura-Kamada K, Mizugaki N, Kishimoto T, Sano T, Nunome H, Williams DE, Andersen RJ, Tanaka K. Phospholipid flippases and Sfk1p, a novel regulator of phospholipid asymmetry, contribute to low permeability of the plasma membrane. Mol Biol Cell 2018. [PMID: 29540528 PMCID: PMC5935070 DOI: 10.1091/mbc.e17-04-0217] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Phospholipid flippase (type 4 P-type ATPase) plays a major role in the generation of phospholipid asymmetry in eukaryotic cell membranes. Loss of Lem3p-Dnf1/2p flippases leads to the exposure of phosphatidylserine (PS) and phosphatidylethanolamine (PE) on the cell surface in yeast, resulting in sensitivity to PS- or PE-binding peptides. We isolated Sfk1p, a conserved membrane protein in the TMEM150/FRAG1/DRAM family, as a multicopy suppressor of this sensitivity. Overexpression of SFK1 decreased PS/PE exposure in lem3Δ mutant cells. Consistent with this, lem3Δ sfk1Δ double mutant cells exposed more PS/PE than the lem3Δ mutant. Sfk1p was previously implicated in the regulation of the phosphatidylinositol-4 kinase Stt4p, but the effect of Sfk1p on PS/PE exposure in lem3Δ was independent of Stt4p. Surprisingly, Sfk1p did not facilitate phospholipid flipping but instead repressed it, even under ATP-depleted conditions. We propose that Sfk1p negatively regulates transbilayer movement of phospholipids irrespective of directions. In addition, we showed that the permeability of the plasma membrane was dramatically elevated in the lem3Δ sfk1Δ double mutant in comparison with the corresponding single mutants. Interestingly, total ergosterol was decreased in the lem3Δ sfk1Δ mutant. Our results suggest that phospholipid asymmetry is required for the maintenance of low plasma membrane permeability.
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Affiliation(s)
- Tetsuo Mioka
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Kita-ku, Sapporo 060-0815, Japan
| | - Konomi Fujimura-Kamada
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Kita-ku, Sapporo 060-0815, Japan
| | - Nahiro Mizugaki
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Kita-ku, Sapporo 060-0815, Japan
| | - Takuma Kishimoto
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Kita-ku, Sapporo 060-0815, Japan
| | - Takamitsu Sano
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Kita-ku, Sapporo 060-0815, Japan
| | - Hitoshi Nunome
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Kita-ku, Sapporo 060-0815, Japan
| | - David E Williams
- Departments of Chemistry and Earth, Ocean, and Atmospheric Sciences, University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Raymond J Andersen
- Departments of Chemistry and Earth, Ocean, and Atmospheric Sciences, University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Kazuma Tanaka
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Kita-ku, Sapporo 060-0815, Japan
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Lv QZ, Qin YL, Yan L, Wang L, Zhang C, Jiang YY. NSG2 ( ORF19.273) Encoding Protein Controls Sensitivity of Candida albicans to Azoles through Regulating the Synthesis of C14-Methylated Sterols. Front Microbiol 2018. [PMID: 29515531 PMCID: PMC5826172 DOI: 10.3389/fmicb.2018.00218] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Antifungal azole drugs inhibit the synthesis of ergosterol and cause the accumulation of sterols containing a 14α-methyl group, which is related to the properties of cell membrane. Due to the frequent recurrence of fungal infections and clinical long-term prophylaxis, azole resistance is increasing rapidly. In our research, Nsg2p, encoded by the ORF19.273 in Candida albicans, is found to be involved in the inhibition of 14α-methylated sterols and resistance to azoles. Under the action of fluconazole, nsg2Δ/Δ mutants are seriously damaged in the integrity and functions of cell membranes with a decrease of ergosterol ratio and an increase of both obtusifoliol and 14α-methylfecosterol ratio. The balance between ergosterol and 14α-methyl sterols mediated by NSG2 plays an important role in C. albicans responding to azoles in vitro as well as in vivo. These phenotypes are completely different from those of Nsg2p in Saccharomyces cerevisiae, which is proved to increase the stability of HMG-CoA and resistance to lovastatin. Based on the evidence above, it is indicated that the decrease of 14α-methylated sterols is an azole-resistant mechanism in C. albicans, which may provide new strategies for overcoming the problems of azole resistance.
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Affiliation(s)
- Quan-Zhen Lv
- Center for New Drug Research, College of Pharmacy, Second Military Medical University, Shanghai, China
| | - Yu-Lin Qin
- Center for New Drug Research, College of Pharmacy, Second Military Medical University, Shanghai, China
| | - Lan Yan
- Center for New Drug Research, College of Pharmacy, Second Military Medical University, Shanghai, China
| | - Liang Wang
- Center for New Drug Research, College of Pharmacy, Second Military Medical University, Shanghai, China
| | - Chuyue Zhang
- Shanghai Pinghe Bilingual School, Shanghai, China
| | - Yuan-Ying Jiang
- Center for New Drug Research, College of Pharmacy, Second Military Medical University, Shanghai, China
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Transcriptomics Sequencing Provides Insights into Understanding the Mechanism of Grass Carp Reovirus Infection. Int J Mol Sci 2018; 19:ijms19020488. [PMID: 29415502 PMCID: PMC5855710 DOI: 10.3390/ijms19020488] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Revised: 01/31/2018] [Accepted: 02/03/2018] [Indexed: 12/13/2022] Open
Abstract
Grass carp is an important aquaculture fish species in China that is affected by severe diseases, especially haemorrhagic disease caused by grass carp reovirus (GCRV). However, the mechanisms of GCRV invasion and infection remain to be elucidated. In the present study, Ctenopharyngodon idellus kidney (CIK) cells were infected with GCRV, harvested at 0, 8, 24, and 72 h post infection, respectively, and then subjected to transcriptomics sequencing. Each sample yielded more than 6 Gb of clean data and 40 million clean reads. To better understand GCRV infection, the process was divided into three phases: the early (0-8 h post infection), middle (8-24 h post infection), and late (24-72 h) stages of infection. A total of 76 (35 up-regulated, 41 down-regulated), 553 (463 up-regulated, 90 down-regulated), and 284 (150 up-regulated, 134 down-regulated) differently expressed genes (DEGs) were identified during the early, middle, and late stages of infection, respectively. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that DEGs were mainly involved in carbohydrate biosynthesis, transport, and endocytosis in the early stage, phagocytosis and lysosome pathways were mainly enriched in the middle stage, and programmed cell death, apoptosis, and inflammation were largely associated with the late stage. These results suggest GCRV infection is a gradual process involving adsorption on the cell surface, followed by endocytosis into cells, transport by lysosomes, and eventually resulted in cell necrosis and/or apoptosis. Our findings provide insight into the mechanisms of grass carp reovirus infection.
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Inafuku M, Basyuni M, Oku H. Triterpenoid modulates the salt tolerance of lanosterol synthase deficient Saccharomyces cerevisiae, GIL77. Saudi J Biol Sci 2018; 25:1-9. [PMID: 29379348 PMCID: PMC5775075 DOI: 10.1016/j.sjbs.2016.10.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 08/05/2016] [Accepted: 10/12/2016] [Indexed: 11/30/2022] Open
Abstract
This study examined the effect of triterpenoid on the salt tolerance of lanosterol synthase deficient yeast mutant GIL77. The expression of the triterpenoid synthase gene under GAL1 promoter in GIL77 increased the triterpenoid concentration of both whole cell and plasma membrane fractions. Without the induction of the genes, the growth curve of BgbAS or RsM1 transformant depicted patterns similar to control cells in both the presence and absence of salt with growth inhibition at 500 mM NaCl. The induction of BgbAS and RsM1 gene expression slightly repressed growth compared with control cells in the absence of NaCl. The growth of GIL77 was significantly suppressed by the expression of BgbAS or RsM1 under salinity conditions. Of the triterpenoid synthase genes, BgbAS rather than RsM1 was found to strongly inhibit the growth of GIL77 cells under salt stressed conditions. The expression of the triterpenoid synthase gene in GIL77 also influenced their tolerance to other abiotic stresses. In contrast to the endogenous synthesis, the exogenous supply of triterpenoid in the culture medium appeared to occur in the plasma membrane fraction and enhanced the salt tolerance of GIL77. This study thus discussed the physiological significance of triterpenoid in relation to its possible role in modulating salt tolerance.
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Key Words
- BgLUS, lupeol synthase
- BgbAS, β-amyrin synthase
- FID, flame ionization detector
- GC, gas chromatography
- GIL77
- LS, lanosterol synthase
- MES, 2-morpholinoethanesulfonic acid
- OSCs, oxidosqualene cyclase
- Oxidosqualene cyclase gene
- RsM1, multifunctional triterpenoid synthase
- S.E.M., standard error of the mean
- SC, synthetic complete
- Salt tolerance
- TLC, thin layer chromatography
- Triterpenoids
- Yeast
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Affiliation(s)
- Masashi Inafuku
- Department of Applied Biological Information, Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan
| | - Mohammad Basyuni
- Department of Forestry, Faculty of Forestry, University of Sumatera Utara, Medan, Indonesia
| | - Hirosuke Oku
- Department of Applied Biological Information, Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan
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Yeast caspase-dependent apoptosis in Saccharomyces cerevisiae BY4742 induced by antifungal and potential antitumor agent clotrimazole. Arch Microbiol 2017; 200:97-106. [PMID: 28819786 DOI: 10.1007/s00203-017-1425-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Revised: 07/25/2017] [Accepted: 08/07/2017] [Indexed: 12/11/2022]
Abstract
Clotrimazole is an antifungal medication commonly used in the treatment of fungal infections. There is also promising research on using clotrimazole against other diseases such as malaria, beriberi, tineapedis and cancer. It was aimed to investigate the apoptotic phenotype in Saccharomyces cerevisiae induced by clotrimazole. The exposure of S. cerevisiae to 10 µM clotrimazole for 3, 6 and 9 h caused to decrease in cell viability by 24.82 ± 0.81, 56.00 ± 1.54 and 77.59 ± 0.53%, respectively. It was shown by Annexin V-PI assay that 110 µM clotrimazole treatment caused to death by 35.5 ± 2.48% apoptotic and only 13.1 ± 0.08% necrotic pathway within 30 min. The occurrence of DNA strand breaks and condensation could be visualised by the TUNEL and DAPI stainings, respectively. Yeast caspase activity was induced 12.34 ± 0.71-fold after 110 µM clotrimazole treatment for 30 min compared to the control. The dependency of clotrimazole-induced apoptosis to caspase was also shown using Δyca1 mutant.
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Anderson MZ, Saha A, Haseeb A, Bennett RJ. A chromosome 4 trisomy contributes to increased fluconazole resistance in a clinical isolate of Candida albicans. MICROBIOLOGY-SGM 2017. [PMID: 28640746 PMCID: PMC5737213 DOI: 10.1099/mic.0.000478] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Candida albicans is an important opportunistic fungal pathogen capable of causing both mucosal and disseminated disease. Infections are often treated with fluconazole, a front-line antifungal drug that targets the biosynthesis of ergosterol, a major component of the fungal cell membrane. Resistance to fluconazole can arise through a variety of mechanisms, including gain-of-function mutations, loss of heterozygosity events and aneuploidy. The clinical isolate P60002 was found to be highly resistant to azole-class drugs, yet lacked mutations or chromosomal rearrangements known to be associated with azole resistance. Transcription profiling suggested that increased expression of two putative drug efflux pumps, CDR11 and QDR1, might confer azole resistance. However, ectopic expression of the P60002 alleles of these genes in a drug-susceptible strain did not increase fluconazole resistance. We next examined whether the presence of three copies of chromosome 4 (Chr4) or chromosome 6 (Chr6) contributed to azole resistance in P60002. We established that Chr4 trisomy contributes significantly to fluconazole resistance, whereas Chr6 trisomy has no discernible effect on resistance. In contrast, a Chr4 trisomy did not increase fluconazole resistance when present in the standard SC5314 strain background. These results establish a link between Chr4 trisomy and elevated fluconazole resistance, and demonstrate the impact of genetic background on drug resistance phenotypes in C. albicans.
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Affiliation(s)
- Matthew Z Anderson
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, 02912, USA
| | - Amrita Saha
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, 02912, USA
| | - Abid Haseeb
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, 02912, USA
| | - Richard J Bennett
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, 02912, USA
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Discovery of Ibomycin, a Complex Macrolactone that Exerts Antifungal Activity by Impeding Endocytic Trafficking and Membrane Function. Cell Chem Biol 2016; 23:1383-1394. [PMID: 27746129 DOI: 10.1016/j.chembiol.2016.08.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 08/10/2016] [Accepted: 08/29/2016] [Indexed: 01/10/2023]
Abstract
Natural products are invaluable historic sources of drugs for infectious diseases; however, the discovery of novel antimicrobial chemical scaffolds has waned in recent years. Concurrently, there is a pressing need for improved therapeutics to treat fungal infections. We employed a co-culture screen to identify ibomycin, a large polyketide macrolactone that has preferential killing activity against Cryptococcus neoformans. Using chemical and genome methods, we determined the structure of ibomycin and identified the biosynthetic cluster responsible for its synthesis. Chemogenomic profiling coupled with cell biological assays link ibomycin bioactivity to membrane function. The preferential activity of ibomycin toward C. neoformans is due to the ability of the compound to selectively permeate its cell wall. These results delineate a novel antifungal agent that is produced by one of the largest documented biosynthetic clusters to date and underscore the fact that there remains significant untapped chemical diversity of natural products with application in antimicrobial research.
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Lv QZ, Yan L, Jiang YY. The synthesis, regulation, and functions of sterols in Candida albicans: Well-known but still lots to learn. Virulence 2016; 7:649-59. [PMID: 27221657 DOI: 10.1080/21505594.2016.1188236] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Sterols are the basal components of the membranes of the fungal pathogen Candida albicans, and these membranes determine the susceptibility of C. albicans cells to a variety of stresses, such as ionic, osmotic and oxidative pressures, and treatment with antifungal drugs. The common antifungal azoles in clinical use are targeted to the biosynthesis of ergosterol. In the past years, the synthesis, storage and metabolism of ergosterol in Saccharomyces cerevisiae has been characterized in some detail; however, these processes has not been as well investigated in the human opportunistic pathogen C. albicans. In this review, we summarize the genes involved in ergosterol synthesis and regulation in C. albicans. As well, genes in S. cerevisiae implicated in ergosterol storage and conversions with other lipids are noted, as these provide us clues and directions for the study of the homologous genes in C. albicans. In this report we have particularly focused on the essential roles of ergosterol in the dynamic process of cell biology and its fundamental status in the biological membrane system that includes lipid rafts, lipid droplets, vacuoles and mitochondria. We believe that a thorough understanding of this classic and essential pathway will give us new ideas about drug resistance and morphological switching in C. albicans.
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Affiliation(s)
- Quan-Zhen Lv
- a Center for New Drug Research, College of Pharmacy, Second Military Medical University , Shanghai , P.R. China
| | - Lan Yan
- a Center for New Drug Research, College of Pharmacy, Second Military Medical University , Shanghai , P.R. China
| | - Yuan-Ying Jiang
- a Center for New Drug Research, College of Pharmacy, Second Military Medical University , Shanghai , P.R. China
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Chromosome-Specific and Global Effects of Aneuploidy in Saccharomyces cerevisiae. Genetics 2016; 202:1395-409. [PMID: 26837754 DOI: 10.1534/genetics.115.185660] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 01/25/2016] [Indexed: 12/20/2022] Open
Abstract
Aneuploidy, an unbalanced karyotype in which one or more chromosomes are present in excess or reduced copy number, causes an array of known phenotypes including proteotoxicity, genomic instability, and slowed proliferation. However, the molecular consequences of aneuploidy are poorly understood and an unbiased investigation into aneuploid cell biology is lacking. We performed high-throughput screens for genes the deletion of which has a synthetic fitness cost in aneuploidy Saccharomyces cerevisiae cells containing single extra chromosomes. This analysis identified genes that, when deleted, decrease the fitness of specific disomic strains as well as those that impair the proliferation of a broad range of aneuploidies. In one case, a chromosome-specific synthetic growth defect could be explained fully by the specific duplication of a single gene on the aneuploid chromosome, highlighting the ability of individual dosage imbalances to cause chromosome-specific phenotypes in aneuploid cells. Deletion of other genes, particularly those involved in protein transport, however, confers synthetic sickness on a broad array of aneuploid strains. Indeed, aneuploid cells, regardless of karyotype, exhibit protein secretion and cell-wall integrity defects. Thus, we were able to use this screen to identify novel cellular consequences of aneuploidy, dependent on both specific chromosome imbalances and caused by many different aneuploid karyotypes. Interestingly, the vast majority of cancer cells are highly aneuploid, so this approach could be of further use in identifying both karyotype-specific and nonspecific stresses exhibited by cancer cells as potential targets for the development of novel cancer therapeutics.
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De-repression of CSP-1 activates adaptive responses to antifungal azoles. Sci Rep 2016; 6:19447. [PMID: 26781458 PMCID: PMC4726075 DOI: 10.1038/srep19447] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 12/14/2015] [Indexed: 01/07/2023] Open
Abstract
Antifungal azoles are the major drugs that are used to treat fungal infections. This study found that in response to antifungal azole stress, Neurospora crassa could activate the transcriptional responses of many genes and increase azole resistance by reducing the level of conidial separation 1 (CSP-1), a global transcription repressor, at azole-responsive genes. The expression of csp-1 was directly activated by the transcription factors WC-1 and WC-2. Upon ketoconazole (KTC) stress, the transcript levels of wc-1 and wc-2 were not changed, but csp-1 transcription rapidly declined. A chromatin immunoprecipitation-quantitative polymerase chain reaction analysis revealed a rapid reduction in the WC-2 enrichment at the csp-1 promoter upon KTC treatment, which might be responsible for the KTC-induced csp-1 downregulation. Deletion of csp-1 increased resistance to KTC and voriconazole, while csp-1 overexpression increased KTC susceptibility. CSP-1 transcriptionally repressed a number of azole-responsive genes, including genes encoding the azole target ERG11, the azole efflux pump CDR4, and the sterol C-22 desaturase ERG5. Deletion of csp-1 also reduced the KTC-induced accumulation of ergosterol intermediates, eburicol, and 14α-methyl-3,6-diol. CSP-1 orthologs are widely present in filamentous fungi, and an Aspergillus fumigatus mutant in which the csp-1 was deleted was resistant to itraconazole.
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Adaptations of the Secretome of Candida albicans in Response to Host-Related Environmental Conditions. EUKARYOTIC CELL 2015; 14:1165-72. [PMID: 26453650 PMCID: PMC4664879 DOI: 10.1128/ec.00142-15] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The wall proteome and the secretome of the fungal pathogen Candida albicans help it to thrive in multiple niches of the human body. Mass spectrometry has allowed researchers to study the dynamics of both subproteomes. Here, we discuss some major responses of the secretome to host-related environmental conditions. Three β-1,3-glucan-modifying enzymes, Mp65, Sun41, and Tos1, are consistently found in large amounts in culture supernatants, suggesting that they are needed for construction and expansion of the cell wall β-1,3-glucan layer and thus correlate with growth and might serve as diagnostic biomarkers. The genes ENG1, CHT3, and SCW11, which encode an endoglucanase, the major chitinase, and a β-1,3-glucan-modifying enzyme, respectively, are periodically expressed and peak in M/G1. The corresponding protein abundances in the medium correlate with the degree of cell separation during single-yeast-cell, pseudohyphal, and hyphal growth. We also discuss the observation that cells treated with fluconazole, or other agents causing cell surface stress, form pseudohyphal aggregates. Fluconazole-treated cells secrete abundant amounts of the transglucosylase Phr1, which is involved in the accumulation of β-1,3-glucan in biofilms, raising the question whether this is a general response to cell surface stress. Other abundant secretome proteins also contribute to biofilm formation, emphasizing the important role of secretome proteins in this mode of growth. Finally, we discuss the relevance of these observations to therapeutic intervention. Together, these data illustrate that C. albicans actively adapts its secretome to environmental conditions, thus promoting its survival in widely divergent niches of the human body.
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Müller C, Binder U, Maurer E, Grimm C, Giera M, Bracher F. Fungal sterol C22-desaturase is not an antimycotic target as shown by selective inhibitors and testing on clinical isolates. Steroids 2015; 101:1-6. [PMID: 26022150 DOI: 10.1016/j.steroids.2015.05.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 05/15/2015] [Accepted: 05/18/2015] [Indexed: 11/25/2022]
Abstract
Inhibition of concise enzymes in ergosterol biosynthesis is one of the most prominent strategies for antifungal chemotherapy. Nevertheless, the enzymes sterol C5-desaturase and sterol C22-desaturase, which introduce double bonds into the sterol core and side chain, have not been fully investigated yet for their potential as antifungal drug targets. Lathosterol side chain amides bearing N-alkyl groups of proper length are known as potent inhibitors of the enzymes sterol C5-desaturase and sterol Δ(24)-reductase in mammalian cholesterol biosynthesis. Here we present the results of our evaluation of these amides for their ability to inhibit enzymes in fungal ergosterol biosynthesis. In the presence of inhibitor(s) an accumulation of sterols lacking a double bond at C22/23 (mainly ergosta-5,7-dien-3β-ol) was observed in Candida glabrata, Saccharomyces cerevisiae, and Yarrowia lipolytica. Hence, the lathosterol side chain amides were identified as selective inhibitors of the fungal sterol C22-desaturase, which was discussed as a specific target for novel antifungals. One representative inhibitor, (3S,20S)-20-N-butylcarbamoylpregn-7-en-3β-ol was subjected to antifungal susceptibility testing on patient isolates according to modified EUCAST guidelines. But, the test organisms showed no significant reduction of cell growth and/or viability up to an inhibitor concentration of 100μg/mL. This leads to the conclusion that sterol C22-desaturase is not an attractive target for the development of antifungals.
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Affiliation(s)
- Christoph Müller
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians University of Munich, Butenandtstr. 5-13, 81377 Munich, Germany.
| | - Ulrike Binder
- Department of Hygiene, Microbiology and Social Medicine, Division of Hygiene and Medical Microbiology, Medical University Innsbruck, Schöpfstr. 41, 6020 Innsbruck, Austria
| | - Elisabeth Maurer
- Department of Hygiene, Microbiology and Social Medicine, Division of Hygiene and Medical Microbiology, Medical University Innsbruck, Schöpfstr. 41, 6020 Innsbruck, Austria
| | - Christian Grimm
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians University of Munich, Butenandtstr. 5-13, 81377 Munich, Germany
| | - Martin Giera
- Leiden University Medical Center, Center for Proteomics and Metabolomics, Albinusdreef 2, 2300 RC Leiden, The Netherlands
| | - Franz Bracher
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians University of Munich, Butenandtstr. 5-13, 81377 Munich, Germany
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Chang W, Zhang M, Li Y, Li X, Gao Y, Xie Z, Lou H. Lichen endophyte derived pyridoxatin inactivates Candida growth by interfering with ergosterol biosynthesis. Biochim Biophys Acta Gen Subj 2015; 1850:1762-71. [PMID: 25960388 DOI: 10.1016/j.bbagen.2015.05.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 04/07/2015] [Accepted: 05/04/2015] [Indexed: 11/18/2022]
Abstract
BACKGROUND This study is to characterize the antifungal effects of pyridoxatin (PYR), a small natural product isolated from an endolichenic fungus. METHODS The susceptibility tests in vitro and in vivo by using Caenorhabditis elegans as an infectious model were performed to evaluate the antifungal efficacy of PYR against Candida species. The cytotoxicity of PYR against normal human cells was tested using MTT assay. The transcriptional levels of genes related to sterol synthesis and cell cycle regulation were measured using real-time quantitative PCR (qPCR). The contents ergosterol, squalene, lanosterol were detected by liquid chromatography/tandem mass spectrometry (LC/MS). RESULTS PYR was effective against four tested Candida species with its minimal inhibitory concentrations (MICs) ranging from 1-4μg/ml. No obvious cytotoxicity was observed for PYR against normal human cells. PYR inhibited the growth of Candida albicans, preventing the biofilm formation. And the antifungal action was independent on efflux pumps. The in vivo test showed PYR greatly prolonged the survival of infected C. elegans. qPCR results revealed that most of the genes related to sterol biosynthesis were considerably down-regulated in PYR-treated cells. Determination of the sterol content found that PYR inhibited the ergosterol synthesis dose dependently and caused the accumulation of squalene and lanosterol. Moreover, analysis of the structure-activity relationship revealed the heterocyclic hydroxamic acid in PYR was the key group for the antifungal action. CONCLUSIONS PYR interferes with the ergosterol synthesis to exert antifungal action. GENERAL SIGNIFICANCE The elucidated mechanism provides possible applications of PYR in fighting clinical relevant fungal infections.
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Affiliation(s)
- Wenqiang Chang
- Department of Natural Product Chemistry, Key Lab of Chemical Biology of Ministry of Education, Shandong University, No. 44 West Wenhua Road, Jinan City, Shandong Province, China
| | - Ming Zhang
- Department of Natural Product Chemistry, Key Lab of Chemical Biology of Ministry of Education, Shandong University, No. 44 West Wenhua Road, Jinan City, Shandong Province, China
| | - Ying Li
- Department of Natural Product Chemistry, Key Lab of Chemical Biology of Ministry of Education, Shandong University, No. 44 West Wenhua Road, Jinan City, Shandong Province, China
| | - Xiaobin Li
- Department of Natural Product Chemistry, Key Lab of Chemical Biology of Ministry of Education, Shandong University, No. 44 West Wenhua Road, Jinan City, Shandong Province, China
| | - Yanhui Gao
- Department of Natural Product Chemistry, Key Lab of Chemical Biology of Ministry of Education, Shandong University, No. 44 West Wenhua Road, Jinan City, Shandong Province, China
| | - Zhiyu Xie
- Department of Natural Product Chemistry, Key Lab of Chemical Biology of Ministry of Education, Shandong University, No. 44 West Wenhua Road, Jinan City, Shandong Province, China
| | - Hongxiang Lou
- Department of Natural Product Chemistry, Key Lab of Chemical Biology of Ministry of Education, Shandong University, No. 44 West Wenhua Road, Jinan City, Shandong Province, China.
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Glucosylceramide Contained in Koji Mold-Cultured Cereal Confers Membrane and Flavor Modification and Stress Tolerance to Saccharomyces cerevisiae during Coculture Fermentation. Appl Environ Microbiol 2015; 81:3688-98. [PMID: 25795678 DOI: 10.1128/aem.00454-15] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 03/16/2015] [Indexed: 01/01/2023] Open
Abstract
In nature, different microorganisms create communities through their physiochemical and metabolic interactions. Many fermenting microbes, such as yeasts, lactic acid bacteria, and acetic acid bacteria, secrete acidic substances and grow faster at acidic pH values. However, on the surface of cereals, the pH is neutral to alkaline. Therefore, in order to grow on cereals, microbes must adapt to the alkaline environment at the initial stage of colonization; such adaptations are also crucial for industrial fermentation. Here, we show that the yeast Saccharomyces cerevisiae, which is incapable of synthesizing glucosylceramide (GlcCer), adapted to alkaline conditions after exposure to GlcCer from koji cereal cultured with Aspergillus kawachii. We also show that various species of GlcCer derived from different plants and fungi similarly conferred alkali tolerance to yeast. Although exogenous ceramide also enhanced the alkali tolerance of yeast, no discernible degradation of GlcCer to ceramide was observed in the yeast culture, suggesting that exogenous GlcCer itself exerted the activity. Exogenous GlcCer also increased ethanol tolerance and modified the flavor profile of the yeast cells by altering the membrane properties. These results indicate that GlcCer from A. kawachii modifies the physiology of the yeast S. cerevisiae and demonstrate a new mechanism for cooperation between microbes in food fermentation.
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