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1.
Mol Microbiol ; 121(4): 696-716, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178569

RESUMO

Candida albicans has the capacity to neutralize acidic growth environments by releasing ammonia derived from the catabolism of amino acids. The molecular components underlying alkalization and its physiological significance remain poorly understood. Here, we present an integrative model with the cytosolic NAD+-dependent glutamate dehydrogenase (Gdh2) as the principal ammonia-generating component. We show that alkalization is dependent on the SPS-sensor-regulated transcription factor STP2 and the proline-responsive activator Put3. These factors function in parallel to derepress GDH2 and the two proline catabolic enzymes PUT1 and PUT2. Consistently, a double mutant lacking STP2 and PUT3 exhibits a severe alkalization defect that nearly phenocopies that of a gdh2-/- strain. Alkalization is dependent on mitochondrial activity and in wild-type cells occurs as long as the conditions permit respiratory growth. Strikingly, Gdh2 levels decrease and cells transiently extrude glutamate as the environment becomes more alkaline. Together, these processes constitute a rudimentary regulatory system that counters and limits the negative effects associated with ammonia generation. These findings align with Gdh2 being dispensable for virulence, and based on a whole human blood virulence assay, the same is true for C. glabrata and C. auris. Using a transwell co-culture system, we observed that the growth and proliferation of Lactobacillus crispatus, a common component of the acidic vaginal microenvironment and a potent antagonist of C. albicans, is unaffected by fungal-induced alkalization. Consequently, although Candida spp. can alkalinize their growth environments, other fungal-associated processes are more critical in promoting dysbiosis and virulent fungal growth.


Assuntos
Aminoácidos , Candida albicans , Feminino , Humanos , Candida albicans/metabolismo , Aminoácidos/metabolismo , Amônia/metabolismo , Candida/metabolismo , Prolina/metabolismo , Candida glabrata/metabolismo
2.
Microb Pathog ; 193: 106773, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38960213

RESUMO

Meyerozyma guilliermondii (Candida guilliermondii) is one of the Candida species associated with invasive candidiasis. With the potential for expressing industrially important enzymes, M. guilliermondii strain SO possessed 99 % proteome similarity with the clinical ATCC 6260 isolate and showed pathogenicity towards zebrafish embryos. Recently, three secreted aspartyl proteinases (SAPs) were computationally identified as potential virulence factors in this strain without in vitro verification of SAP activity. The quantification of Candida SAPs activity in liquid broth were also scarcely reported. Thus, this study aimed to characterize M. guilliermondii strain SO's ability to produce SAPs (MgSAPs) in different conditions (morphology and medium) besides analyzing its growth profile. MgSAPs' capability to cleave bovine serum albumin (BSA) was also determined to propose that MgSAPs as the potential virulence factors compared to the avirulent Saccharomyces cerevisiae. M. guilliermondii strain SO produced more SAPs (higher activity) in yeast nitrogen base-BSA-dextrose broth compared to yeast extract-BSA-dextrose broth despite insignificantly different SAP activity in both planktonic and biofilm cells. FeCl3 supplementation significantly increased the specific protein activity (∼40 %). The BSA cleavage by MgSAPs at an acidic pH was proven through semi-quantitative SDS-PAGE, sharing similar profile with HIV-1 retropepsin. The presented work highlighted the MgSAPs on fungal cell wall and extracellular milieu during host infection could be corroborated to the quantitative production in different growth modes presented herein besides shedding lights on the potential usage of retropepsin's inhibitors in treating candidiasis. Molecular and expression analyses of MgSAPs and their deletion should be further explored to attribute their respective virulence effects.


Assuntos
Ácido Aspártico Proteases , Biofilmes , Candidíase , Soroalbumina Bovina , Fatores de Virulência , Fatores de Virulência/metabolismo , Fatores de Virulência/genética , Ácido Aspártico Proteases/metabolismo , Ácido Aspártico Proteases/genética , Candidíase/microbiologia , Soroalbumina Bovina/metabolismo , Biofilmes/crescimento & desenvolvimento , Animais , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Meios de Cultura/química , Candida/patogenicidade , Candida/metabolismo , Candida/genética , Saccharomycetales/metabolismo , Saccharomycetales/patogenicidade , Saccharomycetales/genética , Virulência
3.
FEMS Yeast Res ; 242024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-39009031

RESUMO

Lignocellulose (dry plant biomass) is an abundant cheap inedible residue of agriculture and wood industry with great potential as a feedstock for biotechnological processes. Lignocellulosic substrates can serve as valuable resources in fermentation processes, allowing the production of a wide array of chemicals, fuels, and food additives. The main obstacle for cost-effective conversion of lignocellulosic hydrolysates to target products is poor metabolism of the major pentoses, xylose and L-arabinose, which are the second and third most abundant sugars of lignocellulose after glucose. We study the oversynthesis of riboflavin in the flavinogenic yeast Candida famata and found that all major lignocellulosic sugars, including xylose and L-arabinose, support robust growth and riboflavin synthesis in the available strains of C. famata. To further increase riboflavin production from xylose and lignocellulose hydrolysate, genes XYL1 and XYL2 coding for xylose reductase and xylitol dehydrogenase were overexpressed. The resulting strains exhibited increased riboflavin production in both shake flasks and bioreactors using diluted hydrolysate, reaching 1.5 g L-1.


Assuntos
Candida , Lignina , Engenharia Metabólica , Riboflavina , Xilose , Lignina/metabolismo , Riboflavina/metabolismo , Riboflavina/biossíntese , Candida/metabolismo , Candida/genética , Xilose/metabolismo , Aldeído Redutase/metabolismo , Aldeído Redutase/genética , Fermentação , Reatores Biológicos/microbiologia , D-Xilulose Redutase/metabolismo , D-Xilulose Redutase/genética , Arabinose/metabolismo
4.
J Appl Microbiol ; 135(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38565314

RESUMO

AIMS: Ethyl hexanoate, one of the key flavor compounds in strong-flavor Baijiu. To improve the content of ethyl hexanoate in strong-flavor Baijiu, a functional strain with high yield of ethyl hexanoate was screened and its ester-producing performance was studied. METHODS AND RESULTS: Upon identification, the strain was classified as Candida sp. and designated as ZY002. Under optimal fermentation conditions, the content of ethyl hexanoate synthesized by ZY002 can be as high as 170.56 mg L-1. A fermentation test was carried out using the ZY002 strain bioaugmented Daqu to verify the role of the strain applied to Baijiu brewing. It was found that strain ZY002 could not only improve the moisture and alcohol contents of fermented grains but also diminish the presence of reducing sugar and crude starch. Furthermore, it notably amplified the abundance of flavor compounds. CONCLUSION: In this study, Candida sp. ZY002 with a high yield of ethyl hexanoate provided high-quality strain resources for the actual industrial production of Baijiu.


Assuntos
Candida , Caproatos , Ésteres , Fermentação , Alimentos Fermentados , Caproatos/metabolismo , Ésteres/metabolismo , Ésteres/análise , Alimentos Fermentados/microbiologia , Alimentos Fermentados/análise , Candida/metabolismo , Aromatizantes/metabolismo , Microbiologia de Alimentos , Bebidas Alcoólicas/microbiologia , Bebidas Alcoólicas/análise
5.
Food Microbiol ; 123: 104584, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39038890

RESUMO

A single strain of Candida anglica, isolated from cider, is available in international yeast collections. We present here seven new strains isolated from French PDO cheeses. For one of the cheese strains, we achieved a high-quality genome assembly of 13.7 Mb with eight near-complete telomere-to-telomere chromosomes. The genomes of two additional cheese strains and of the cider strain were also assembled and annotated, resulting in a core genome of 5966 coding sequences. Phylogenetic analysis showed that the seven cheese strains clustered together, away from the cider strain. Mating-type locus analysis revealed the presence of a MATa locus in the cider strain but a MATalpha locus in all cheese strains. The presence of LINE retrotransposons at identical genome position in the cheese strains, and two different karyotypic profiles resulting from chromosomal rearrangements were observed. Together, these findings are consistent with clonal propagation of the cheese strains. Phenotypic trait variations were observed within the cheese population under stress conditions whereas the cider strain was found to have a much greater capacity for growth in all conditions tested.


Assuntos
Candida , Queijo , Alimentos Fermentados , Genoma Fúngico , Filogenia , Queijo/microbiologia , Candida/genética , Candida/metabolismo , Candida/classificação , Candida/isolamento & purificação , Candida/crescimento & desenvolvimento , Alimentos Fermentados/microbiologia , Adaptação Fisiológica , Microbiologia de Alimentos , Fermentação , Genes Fúngicos Tipo Acasalamento
6.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33723044

RESUMO

Candida albicans is the most common cause of systemic fungal infections in humans and is considerably more virulent than its closest known relative, Candida dubliniensis. To investigate this difference, we constructed interspecies hybrids and quantified mRNA levels produced from each genome in the hybrid. This approach systematically identified expression differences in orthologous genes arising from cis-regulatory sequence changes that accumulated since the two species last shared a common ancestor, some 10 million y ago. We documented many orthologous gene-expression differences between the two species, and we pursued one striking observation: All 15 genes coding for the enzymes of glycolysis showed higher expression from the C. albicans genome than the C. dubliniensis genome in the interspecies hybrid. This pattern requires evolutionary changes to have occurred at each gene; the fact that they all act in the same direction strongly indicates lineage-specific natural selection as the underlying cause. To test whether these expression differences contribute to virulence, we created a C. dubliniensis strain in which all 15 glycolysis genes were produced at modestly elevated levels and found that this strain had significantly increased virulence in the standard mouse model of systemic infection. These results indicate that small expression differences across a deeply conserved set of metabolism enzymes can play a significant role in the evolution of virulence in fungal pathogens.


Assuntos
Evolução Biológica , Candida/classificação , Candida/genética , Seleção Genética , Alelos , Candida/metabolismo , Candida/patogenicidade , Candidíase/microbiologia , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Ontologia Genética , Genes Fúngicos , Hibridização Genética , Virulência/genética
7.
J Insect Sci ; 24(3)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38713543

RESUMO

The black soldier fly, Hermetia illucens L. (Diptera: Stratiomyidae), is commonly used for organic waste recycling and animal feed production. However, the often inadequate nutrients in organic waste necessitate nutritional enhancement of black soldier fly larvae, e.g., by fungal supplementation of its diet. We investigated the amino acid composition of two fungi, Candida tropicalis (Castell.) Berkhout (Saccharomycetales: Saccharomycetaceae) and Pichia kudriavzevii Boidin, Pignal & Besson (Saccharomycetales: Pichiaceae), from the black soldier fly gut, and commercial baker's yeast, Saccharomyces cerevisiae Meyen ex E.C. Hansen (Saccharomycetales: Saccharomycetaceae), and their effects on larval growth and hemolymph metabolites in fifth-instar black soldier fly larvae. Liquid chromatography-mass spectrometry was used to study the effect of fungal metabolites on black soldier fly larval metabolism. Amino acid analysis revealed significant variation among the fungi. Fungal supplementation led to increased larval body mass and differential metabolite accumulation. The three fungal species caused distinct metabolic changes, with each over-accumulating and down-accumulating various metabolites. We identified significant alteration of histidine metabolism, aminoacyl-tRNA biosynthesis, and glycerophospholipid metabolism in BSF larvae treated with C. tropicalis. Treatment with P. kudriavzevii affected histidine metabolism and citrate cycle metabolites, while both P. kudriavzevii and S. cerevisiae treatments impacted tyrosine metabolism. Treatment with S. cerevisiae resulted in down-accumulation of metabolites related to glycine, serine, and threonine metabolism. This study suggests that adding fungi to the larval diet significantly affects black soldier fly larval metabolomics. Further research is needed to understand how individual amino acids and their metabolites contributed by fungi affect black soldier fly larval physiology, growth, and development, to elucidate the interaction between fungal nutrients and black soldier fly physiology.


Assuntos
Dípteros , Hemolinfa , Larva , Animais , Larva/crescimento & desenvolvimento , Larva/metabolismo , Dípteros/metabolismo , Dípteros/crescimento & desenvolvimento , Hemolinfa/metabolismo , Pichia/metabolismo , Saccharomyces cerevisiae/metabolismo , Aminoácidos/metabolismo , Dieta , Saccharomycetales/metabolismo , Ração Animal/análise , Candida/metabolismo , Candida/crescimento & desenvolvimento
8.
J Environ Manage ; 362: 121351, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38838535

RESUMO

In this study, the growth of yeast and yeast-like fungi in the liquid digestate from vegetable wastes was investigated in order to remove nutrients and organic pollutants, and for their application as co-culture members with green microalgae. The studied yeast strains were characterized for their assimilative and enzymatic profiles as well as temperature requirements. In the first experimental stage, the growth dynamics of each strain were determined, allowing to select the best yeasts for further studies. In the subsequent stage, the ability of selectants to remove organic pollutants was assessed. Different cultivation media containing respectively 1:3, 1:1, 3:1 vol ratio of liquid digestate and the basal minimal medium were used. Among all tested yeast strains, Rhodotorula mucilaginosa DSM 70825 showed the most promising results, demonstrating the highest potential for removing organic substrates and nutrients. Depending on the medium, this strain achieved 50-80% sCOD, 45-60% tVFAs, 21-45% TN, 33-52% PO43- reduction rates. Similar results were obtained for the strain Candida sp. OR687571. The high nutrient and organics removal efficiency by these yeasts could likely be linked to their ability to assimilate xylose (being the main source of carbon in the liquid digestate). In culture media containing liquid digestate, both yeast strains achieved good viability and proliferation potential. In the liquid digestate medium, R. mucilaginosa and Candida sp. showed vitality at the level of 51.5% and 45.0%, respectively. These strains seem to be a good starting material for developing effective digestate treatment strategies involving monocultures and/or consortia with other yeasts or green microalgae.


Assuntos
Técnicas de Cocultura , Microalgas , Leveduras , Microalgas/crescimento & desenvolvimento , Microalgas/metabolismo , Leveduras/metabolismo , Leveduras/crescimento & desenvolvimento , Rhodotorula/metabolismo , Rhodotorula/crescimento & desenvolvimento , Nutrientes/metabolismo , Biodegradação Ambiental , Candida/crescimento & desenvolvimento , Candida/metabolismo
9.
Metab Eng ; 77: 76-88, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36948241

RESUMO

Candida viswanathii is a promising cell factory for producing dodecanedioic acid (DDA) and other long chain dicarboxylic acids. However, metabolic engineering of C. viswanathii is difficult partly due to the lack of synthetic biology toolkits. Here we developed CRISPR-based approaches for rational genome and metabolic engineering of C. viswanathii. We first optimized the CRISPR system and protocol to promote the homozygous gene integration efficiency to >60%. We also designed a split CRISPR system for one-step integration of multiple genes into C. viswanathii. We uncovered that co-expression of CYP52A19, CPRb and FAO2 that catalyze different steps in the biotransformation enhances DDA production and abolishes accumulation of intermediates. We also unveiled that co-expression of additional enzyme POS5 further promotes DDA production and augments cell growth. We harnessed the split CRISPR system to co-integrate these 4 genes (13.6 kb) into C. viswanathii and generated a stable strain that doubles the DDA titer (224 g/L), molar conversion (83%) and productivity (1.87 g/L/h) when compared with the parent strain. This study altogether identifies appropriate enzymes/promoters to augment dodecane conversion to DDA and implicates the potential of split CRISPR system for metabolic engineering of C. viswanathii.


Assuntos
Candida , Engenharia Metabólica , Candida/genética , Candida/metabolismo , Ácidos Dicarboxílicos/metabolismo , Sistemas CRISPR-Cas
10.
Lett Appl Microbiol ; 76(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36688769

RESUMO

Pichia and Candida species include biofilm-forming yeasts able to spoil foods and beverages. Strains belonging to 10 Pichia and Candida species isolated from apples, grape musts, and wines were analysed. They were subjected to molecular typing and characterized for their ability to grow and ferment must for cider and wine production, and for their biofilm properties. All strains grew similarly in apple and grape must. Glucose-fermenting strains displayed differentiated fermentation performances. Great variation in SO2 and ethanol sensitivity was observed among the strains. Pichia manshurica strains showed high tolerance to both molecules. Eleven and five surface-spreading biofilm (MAT) phenotypes were identified in solid and liquid media, respectively. Strains produced biofilms with variable thicknesses and widths in culture tubes. Cell adherence and aqueous-hydrocarbon biphasic hydrophobicity assays were carried out. Some Pichia manshurica and P. membranifaciens strains exhibited a high capacity to form a thick biofilm and had high cell adherence and hydrophobicity values. These strains could be more likely to colonize the internal surfaces of tanks. This study evidenced that some Pichia and Candida strains can proliferate during apple and grape must fermentation and may be detrimental the beverage quality, due to their specific biofilm properties.


Assuntos
Malus , Vitis , Vinho , Pichia/metabolismo , Candida/metabolismo , Vitis/metabolismo , Leveduras/metabolismo , Vinho/análise , Fermentação
11.
J Environ Manage ; 325(Pt B): 116657, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36335696

RESUMO

The safe and robust yeast Candida utilis was employed for nitrogen recovery as single cell protein from biogas slurry. The maximum biomass of 6.2 g/L with protein content of 53.5% was produced in batch cultivation with glucose as the carbon source, C/N ratio of 3:1, NH4+-N concentration of 3000 mg/L, initial pH of 8.0, and the addition of 0.35% (w/v) Na2HPO4. It was speculated that C. utilis can grow well with free ammonia below 197 mg/L. In fed-batch fermentation, a biomass of 14.8 g/L was obtained, and the maintenance of aerobic conditions was critical to improving the production of single cell protein. The sterilized and non-sterilized biogas slurry can be used as an effective pH regulator. The obtained single cell protein was a nutritious, safe, and reliable protein source. This study provides novel insights into nitrogen recovery via C. utilis as a single cell protein from biogas slurry.


Assuntos
Amônia , Biocombustíveis , Amônia/metabolismo , Candida/metabolismo , Nitrogênio/metabolismo , Biomassa
12.
Molecules ; 28(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36677748

RESUMO

Invasive fungal infections represent a public health problem that worsens over the years with the increasing resistance to current antimycotic agents. Therefore, there is a compelling medical need of widening the antifungal drug repertoire, following different methods such as drug repositioning, identification and validation of new molecular targets and developing new inhibitors against these targets. In this work we developed a structure-based strategy for drug repositioning and new drug design, which can be applied to infectious fungi and other pathogens. Instead of applying the commonly accepted off-target criterion to discard fungal proteins with close homologues in humans, the core of our approach consists in identifying fungal proteins with active sites that are structurally similar, but preferably not identical to binding sites of proteins from the so-called "human pharmacolome". Using structural information from thousands of human protein target-inhibitor complexes, we identified dozens of proteins in fungal species of the genera Histoplasma, Candida, Cryptococcus, Aspergillus and Fusarium, which might be exploited for drug repositioning and, more importantly, also for the design of new fungus-specific inhibitors. As a case study, we present the in vitro experiments performed with a set of selected inhibitors of the human mitogen-activated protein kinases 1/2 (MEK1/2), several of which showed a marked cytotoxic activity in different fungal species.


Assuntos
Antifúngicos , Micoses , Humanos , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Candida/metabolismo , Proteínas Fúngicas/química , Domínio Catalítico , Fungos/metabolismo
13.
J Sci Food Agric ; 103(15): 7849-7861, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37467367

RESUMO

BACKGROUND: Pine sterol ester is a type of novel food source nutrient with great advantages in lowering blood cholesterol levels, inhibiting tumors, preventing prostate enlargement, and regulating immunity. Macroporous resins with large specific surface area, stable structures, and various functional groups (epoxy, amino, and octadecyl groups) have been selected for immobilization of Candida rugosa lipase (CRL) to improve its stability and efficiency in the synthesis of pine sterol esters. A solvent-free strategy using oleic acid (substrate) as an esterification reaction medium is an important alternative for avoiding the use of organic solvents. RESULTS: The immobilization conditions of CRL immobilized on several types of commercial macroporous resins were optimized. Fortunately, by adsorption (hydrophobic interaction), a high immobilization efficiency of CRL was obtained using macroporous resins with hydrophobic octadecyl groups with an immobilization efficiency of 86.5%, enzyme loading of 138.5 mg g-1 and enzyme activity of 34.7 U g-1 . The results showed that a 95.1% yield could be obtained with a molar ratio of oleic acid to pine sterol of 5:1, an enzyme amount of 6.0 U g-1 (relative to pine sterol mass) at 50 °C for 48 h. CONCLUSION: The hydrophobic macroporous resin (ECR8806M) with a large specific surface area and abundant functional groups was used to achieve efficient immobilization of CRL. CRL@ECR8806M is an efficient catalyst for the synthesis of phytosterol esters and has the potential for further large-scale applications. Therefore, this simple, green, and low-cost strategy for lipase immobilization provides new possibilities for the high-efficiency production of pine sterol esters and other food source nutrients. © 2023 Society of Chemical Industry.


Assuntos
Enzimas Imobilizadas , Lipase , Lipase/química , Solventes/química , Enzimas Imobilizadas/química , Ácido Oleico , Biocatálise , Candida/metabolismo , Esteróis , Interações Hidrofóbicas e Hidrofílicas , Estabilidade Enzimática , Ésteres
14.
Mol Microbiol ; 115(1): 116-130, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33319423

RESUMO

Transcription factor Mrr1, best known for its regulation of Candida azole resistance genes such as MDR1, regulates other genes that are poorly characterized. Among the other Mrr1-regulated genes are putative methylglyoxal reductases. Methylglyoxal (MG) is a toxic metabolite that is elevated in diabetes, uremia, and sepsis, which are diseases that increase the risk for candidiasis, and MG serves as a regulatory signal in diverse organisms. Our studies in Clavispora lusitaniae, also known as Candida lusitaniae, showed that Mrr1 regulates expression of two paralogous MG reductases, MGD1 and MGD2, and that both participate in MG resistance and MG catabolism. Exogenous MG increased Mrr1-dependent expression of MGD1 and MGD2 as well as expression of MDR1, which encodes an efflux pump that exports fluconazole. MG improved growth in the presence of fluconazole and this was largely Mrr1-dependent with contributions from a secondary transcription factor, Cap1. Increased fluconazole resistance was also observed in mutants lacking Glo1, a Mrr1-independent MG catabolic enzyme. Isolates from other Candida species displayed heterogeneity in MG resistance and MG stimulation of azole resistance. We propose endogenous and host-derived MG can induce MDR1 and other Mrr1-regulated genes causing increased drug resistance, which may contribute to some instances of fungal treatment failure.


Assuntos
Farmacorresistência Fúngica/genética , Aldeído Pirúvico/metabolismo , Saccharomycetales/metabolismo , Antifúngicos/farmacologia , Candida/genética , Candida/metabolismo , Candidíase/tratamento farmacológico , Candidíase/genética , Enzimas de Restrição do DNA/genética , Enzimas de Restrição do DNA/metabolismo , Fluconazol/farmacologia , Proteínas Fúngicas/metabolismo , Expressão Gênica/genética , Regulação Fúngica da Expressão Gênica/genética , Genes Reguladores/genética , Saccharomycetales/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
15.
Appl Environ Microbiol ; 88(4): e0223721, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-34936835

RESUMO

Multiple studies have found that streptococci have a synergistic relationship with Candida species, but the details of these interactions are still being discovered. Candida species are covered by mannan, a polymer of mannose, which could serve as a carbon source for certain microbes. We hypothesized that streptococci that possess mannan-degrading glycosyl hydrolases would be able to enzymatically cleave mannose residues, which could serve as a primary carbohydrate source to support growth. We analyzed 90 streptococcus genomes to predict the capability of streptococci to transport and utilize mannose and to degrade diverse mannose linkages found on mannan. The genome analysis revealed mannose transporters and downstream pathways in most streptococci, but only <50% of streptococci harbored the glycosyl hydrolases required for mannan degradation. To confirm the ability of streptococci to use mannose or mannan, we grew 6 representative streptococci in a chemically defined medium lacking glucose supplemented with mannose, yeast extract, or purified mannan isolated from Candida and Saccharomyces strains. Although all tested Streptococcus strains could use mannose, Streptococcus salivarius and Streptococcus agalactiae, which did not possess mannan-degrading glycosyl hydrolases, could not use yeast extract or mannan to enhance their growth. In contrast, we found that Streptococcus mitis, Streptococcus parasanguinis, Streptococcus sanguinis, and Streptococcus pyogenes possessed the necessary glycosyl hydrolases to use yeast extract and isolated mannan, which promoted robust growth. Our data indicate that several streptococci are capable of degrading fungal mannans and harvesting mannose for energy. IMPORTANCE This work highlights a previously undescribed aspect of streptococcal Candida interactions. Our work identifies that certain streptococci possess the enzymes required to degrade mannan, and through this mechanism, they can release mannose residues from the cell wall of fungal species and use them as a nutrient source. We speculate that streptococci that can degrade fungal mannan may have a competitive advantage for colonization. This finding has broad implications for human health, as streptococci and Candida are found at multiple body sites.


Assuntos
Candida , Mananas , Candida/metabolismo , Parede Celular/metabolismo , Humanos , Mananas/metabolismo , Manose , Streptococcus/metabolismo
16.
Arch Microbiol ; 204(6): 346, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35608680

RESUMO

Lectins participate in the defense against microorganisms and in signaling the damage caused by pathogens to the cell surface and/or intracellular in plants. This study aims to analyze the antifungal potential of lectins extracted from seeds of Canavalia ensiformis (L.) DC and Canavalia rosea (Sw.) DC, against Candida albicans and Candida tropicalis. The antimicrobial tests were performed by microdilution against Candida spp. The test to verify the combined lectin/fluconazole effect was performed using subinhibitory concentrations of lectins and with antifungal ranging from 0.5 to 512 µg/mL. The ability to inhibit the morphological transition of Candida spp. was evaluated by microcultivation in a moist chamber. The results of the minimum inhibitory concentration revealed no antifungal activity against the tested strains. However, lectins modified the action of fluconazole, reducing the IC50 of the drug against C. albicans. Lectins were also able to discretely modulate the morphological transition of the tested strains.


Assuntos
Candida albicans , Candida tropicalis , Antifúngicos/farmacologia , Canavalia/metabolismo , Candida/metabolismo , Concanavalina A , Fluconazol/farmacologia , Lectinas/farmacologia , Testes de Sensibilidade Microbiana , Plâncton
17.
Biotechnol Lett ; 44(1): 89-99, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34738223

RESUMO

OBJECTIVES: To immobilize Candida rugosa lipase in Accurel MP 1000 (CRL-AMP) by physical adsorption in organic medium and apply in the synthesis of wax esters dodecanoyl octadecanoate 1 and hexadecanoyl octadecanoate 2 in a heptane medium, as well as evaluating the stability and recyclability of CRL-AMP in six reaction cycles. RESULTS: The specific activity (Asp) for CRL-AMP was 200 ± 20 U mg-1. Its catalytic activity was 1300 ± 100 U g-1. CRL-AMP was used in the synthesis of esters in heptane medium with a 1:1 acid:alcohol molar ratio at 45 °C and 200 rpm. In synthesis 1, conversion was 62.5 ± 3.9% in 30 min at 10% m v-1 and 56.9 ± 2.8% in 54 min at 5% m v-1; while in synthesis 2, conversion was 79.0 ± 3.9% in 24 min at 10% m v-1, and 46.0 ± 2.4% in 54 min at 5% m v-1. Reuse tests after six consecutive cycles of reaction showed that the biocatalyst retained approximately 50% of its original activity for both reaction systems. CONCLUSIONS: CRL-AMP showed a high potential in the production of wax esters, since it started from low enzymatic load and high specific activities and conversions were obtained, in addition to allowing an increase in stability and recyclability of the prepared biocatalyst.


Assuntos
Ésteres , Lipase , Biocatálise , Candida/metabolismo , Emolientes , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Esterificação , Lipase/metabolismo , Saccharomycetales
18.
J Enzyme Inhib Med Chem ; 37(1): 876-894, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35296203

RESUMO

With increasing number of immunocompromised patients as well as drug resistance in fungi, the risk of fatal fungal infections in humans increases as well. The action of echinocandins is based on the inhibition of ß-(1,3)-d-glucan synthesis that builds the fungal cell wall. Caspofungin, micafungin, anidulafungin and rezafungin are semi-synthetic cyclic lipopeptides. Their specific chemical structure possess a potential to obtain novel derivatives with better pharmacological properties resulting in more effective treatment, especially in infections caused by Candida and Aspergillus species. In this review we summarise information about echinocandins with closer look on their chemical structure, mechanism of action, drug resistance and usage in clinical practice. We also introduce actual trends in modification of this antifungals as well as new methods of their administration, and additional use in viral and bacterial infections.


Assuntos
Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Candida/efeitos dos fármacos , Desenho de Fármacos , Equinocandinas/farmacologia , Antifúngicos/química , Aspergillus/metabolismo , Candida/metabolismo , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Equinocandinas/química , Glucanos/antagonistas & inibidores , Glucanos/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular
19.
Chem Biodivers ; 19(3): e202100757, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35092349

RESUMO

Candida species are responsible for causing invasive candidiasis with high mortality rate and their resistance to available antifungal drugs is a major clinical challenge. Biotransformation process of the labdane diterpene ent-labd-8(17)-en-15,18-dioic acid (1) carried out with Cunninghamella elegans afforded five new derivatives (compounds 2-6). Unusual regioselective hydroxylation of the methyl group at the C-20 position of labdane-type diterpene was achieved and all compounds were subjected to cytotoxicity and antifungal evaluations. Compound 1 and its derivatives were not cytotoxic to normal (MCF-10A) and tumor (MCF-7) cell lines. Compounds 2 and 3 exhibited fungistatic activity against all tested Candida strains at lower concentrations than fluconazole. Both compounds also showed the strongest fungicidal activity against C. albicans, which is the most prevalent fungal agent involved in candidemia.


Assuntos
Candida , Diterpenos , Antifúngicos/farmacologia , Biotransformação , Candida/metabolismo , Cunninghamella , Diterpenos/metabolismo , Diterpenos/farmacologia , Fluconazol , Testes de Sensibilidade Microbiana
20.
Bioprocess Biosyst Eng ; 45(7): 1149-1162, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35585433

RESUMO

Lipases (E.C. 3.1.1.3) have buried active sites and used access tunnels in the transport of substrates and products for biotransformation processes. Computational methods are used to predict the trajectory and energy profile of ligands through these tunnels, and they complement the experimental methodologies because they filter data, optimizing laboratory time and experimental costs. Access tunnels of Burkholderia cepacia lipase (BCL), Candida rugosa lipase (CRL), and porcine pancreas lipase (PPL) and the transport of fatty acids, alcohols and esters through the tunnels were evaluated using the online server CaverWeb V1.0, and server calculation results were compared with experimental data (productivity). BCL showed higher productivity with palmitic acid-C16:0 (4029.95 µmol/h mg); CRL obtained productivity for oleic acid-C18:1 (380.80 µmol/h mg), and PPL achieved productivity for lauric acid-C12:0 (71.27 µmol/h mg). The highest probability of transport for BCL is through the tunnels 1 and 2, for CRL through the tunnel 1, and for PPL through the tunnels 1, 2, 3 and 4. Thus, the best in silico result was the transport of the substrates palmitic acid and ethanol and product ethyl palmitate in tunnel 1 of BCL. This result corroborates with the best result for the productivity data (higher productivity for BCL with palmitic acid-4029.95 µmol/h mg). The combination of in silico evaluation and experimental data gave similar results, demonstrating that in silico approaches are a promising alternative for reducing screening tests and minimizing laboratory time in the bio-catalysis area by identifying the lipases with the greatest reaction potential, as in the case of this proposal.


Assuntos
Burkholderia cepacia , Lipase , Animais , Candida/metabolismo , Lipase/química , Ácido Oleico , Ácidos Palmíticos , Suínos
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