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Vaginal Isolates of Candida glabrata Are Uniquely Susceptible to Ionophoric Killer Toxins Produced by Saccharomyces cerevisiae. Antimicrob Agents Chemother 2021; 65:e0245020. [PMID: 33972245 PMCID: PMC8218651 DOI: 10.1128/aac.02450-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Compared to other species of Candida yeasts, the growth of Candida glabrata is inhibited by many different strains of Saccharomyces killer yeasts. The ionophoric K1 and K2 killer toxins are broadly inhibitory to all clinical isolates of C. glabrata from patients with recurrent vulvovaginal candidiasis, despite high levels of resistance to clinically relevant antifungal therapeutics.
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2
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Fernández de Ullivarri M, Bulacios GA, Navarro SA, Lanza L, Mendoza LM, Chalón MC. The killer yeast Wickerhamomyces anomalus Cf20 exerts a broad anti-Candida activity through the production of killer toxins and volatile compounds. Med Mycol 2021; 58:1102-1113. [PMID: 32196549 DOI: 10.1093/mmy/myaa011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 01/07/2020] [Accepted: 03/04/2020] [Indexed: 01/02/2023] Open
Abstract
Candidiasis is a group of opportunistic infections caused by yeast of the genus Candida. The appearance of drug resistance and the adverse effects of current antifungal therapies require the search for new, more efficient therapeutic alternatives. Killer yeasts have aroused as suitable candidates for mining new antifungal compounds. Killer strains secrete antimicrobial proteins named killer toxins, with promissory antifungal activity. Here we found that the killer yeast Wickerhamomyces anomalus Cf20 and its cell-free supernatant (CFS) inhibited six pathogenic strains and one collection strain of Candida spp. The inhibition is mainly mediated by secreted killer toxins and, to a lesser extent, by volatile compounds such as acetic acid and ethyl acetate. A new large killer toxin (>180 kDa) was purified, which exerted 70-74% of the total CFS anti-Candida activity, and the previously described glucanase KTCf20 was inhibitory in a lesser extent as well. In addition, we demonstrated that Cf20 possesses the genes encoding for the β-1,3-glucanases WaExg1 and WaExg2, proteins with extensively studied antifungal activity, particularly WaExg2. Finally, the 10-fold concentrated CFS exerted a high candidacidal effect at 37°C, completely inhibiting the fungal growth, although the nonconcentrated CFS (RCF 1) had very limited fungistatic activity at this temperature. In conclusion, W. anomalus Cf20 produces different low and high molecular weight compounds with anti-Candida activity that could be used to design new therapies for candidiasis and as a source for novel antimicrobial compounds as well.
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Affiliation(s)
- Miguel Fernández de Ullivarri
- Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT) e Instituto de Química Biológica "Dr. Bernabé Bloj," Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Chacabuco 461, San Miguel de Tucumán. Argentina
| | - Gabriela A Bulacios
- Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT) e Instituto de Química Biológica "Dr. Bernabé Bloj," Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Chacabuco 461, San Miguel de Tucumán. Argentina
| | - Silvia A Navarro
- Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT) e Instituto de Química Biológica "Dr. Bernabé Bloj," Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Chacabuco 461, San Miguel de Tucumán. Argentina
| | - Lucía Lanza
- Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT) e Instituto de Química Biológica "Dr. Bernabé Bloj," Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Chacabuco 461, San Miguel de Tucumán. Argentina
| | - Lucia M Mendoza
- Centro de referencia para lactobacilos (CERELA, CONICET), Chacabuco 145, 4000, Tucumán, Argentina
| | - Miriam C Chalón
- Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT) e Instituto de Química Biológica "Dr. Bernabé Bloj," Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Chacabuco 461, San Miguel de Tucumán. Argentina
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Fredericks LR, Lee MD, Crabtree AM, Boyer JM, Kizer EA, Taggart NT, Roslund CR, Hunter SS, Kennedy CB, Willmore CG, Tebbe NM, Harris JS, Brocke SN, Rowley PA. The Species-Specific Acquisition and Diversification of a K1-like Family of Killer Toxins in Budding Yeasts of the Saccharomycotina. PLoS Genet 2021; 17:e1009341. [PMID: 33539346 PMCID: PMC7888664 DOI: 10.1371/journal.pgen.1009341] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 02/17/2021] [Accepted: 01/05/2021] [Indexed: 12/24/2022] Open
Abstract
Killer toxins are extracellular antifungal proteins that are produced by a wide variety of fungi, including Saccharomyces yeasts. Although many Saccharomyces killer toxins have been previously identified, their evolutionary origins remain uncertain given that many of these genes have been mobilized by double-stranded RNA (dsRNA) viruses. A survey of yeasts from the Saccharomyces genus has identified a novel killer toxin with a unique spectrum of activity produced by Saccharomyces paradoxus. The expression of this killer toxin is associated with the presence of a dsRNA totivirus and a satellite dsRNA. Genetic sequencing of the satellite dsRNA confirmed that it encodes a killer toxin with homology to the canonical ionophoric K1 toxin from Saccharomyces cerevisiae and has been named K1-like (K1L). Genomic homologs of K1L were identified in six non-Saccharomyces yeast species of the Saccharomycotina subphylum, predominantly in subtelomeric regions of the genome. When ectopically expressed in S. cerevisiae from cloned cDNAs, both K1L and its homologs can inhibit the growth of competing yeast species, confirming the discovery of a family of biologically active K1-like killer toxins. The sporadic distribution of these genes supports their acquisition by horizontal gene transfer followed by diversification. The phylogenetic relationship between K1L and its genomic homologs suggests a common ancestry and gene flow via dsRNAs and DNAs across taxonomic divisions. This appears to enable the acquisition of a diverse arsenal of killer toxins by different yeast species for potential use in niche competition.
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Affiliation(s)
- Lance R. Fredericks
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Mark D. Lee
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Angela M. Crabtree
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Josephine M. Boyer
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Emily A. Kizer
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Nathan T. Taggart
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Cooper R. Roslund
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Samuel S. Hunter
- iBEST Genomics Core, University of Idaho, Moscow, Idaho, United States of America
| | - Courtney B. Kennedy
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Cody G. Willmore
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Nova M. Tebbe
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Jade S. Harris
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Sarah N. Brocke
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Paul A. Rowley
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
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Nascimento BL, Delabeneta MF, Rosseto LRB, Junges DSB, Paris AP, Persel C, Gandra RF. Yeast Mycocins: a great potential for application in health. FEMS Yeast Res 2020; 20:5818766. [PMID: 32275311 DOI: 10.1093/femsyr/foaa016] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 04/03/2020] [Indexed: 01/10/2023] Open
Abstract
Mycocins have demonstrated inhibition of fungi, bacteria, parasites and viruses, in addition to being studied as epidemiological markers and in the development of vaccines. They are defined as extracellular proteins or glycoproteins with different activities, the main mechanism of action being the inhibition of β-glucan synthesis in the cell wall of sensitive strains. Given the resistance problems created by several microorganisms to agents commonly used in clinical practice, the discovery of new substances with this purpose becomes essential. Mycocins have potential as anti-microbials because they show minimal toxicity and do not present resistance.
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Affiliation(s)
- Bruna L Nascimento
- Department of Medical and Pharmaceutical Sciences, Avenida Tancredo Neves 3224 CEP: 85806-470, Cascavel, Paraná, Brazil
| | - Mateus F Delabeneta
- Department of Medical and Pharmaceutical Sciences, Avenida Tancredo Neves 3224 CEP: 85806-470, Cascavel, Paraná, Brazil
| | - Lana Rubia B Rosseto
- Department of Medical and Pharmaceutical Sciences, Avenida Tancredo Neves 3224 CEP: 85806-470, Cascavel, Paraná, Brazil
| | - Daniele S B Junges
- Department of Medical and Pharmaceutical Sciences, Avenida Tancredo Neves 3224 CEP: 85806-470, Cascavel, Paraná, Brazil
| | - Ana Paula Paris
- Department of Medical and Pharmaceutical Sciences, Avenida Tancredo Neves 3224 CEP: 85806-470, Cascavel, Paraná, Brazil
| | - Cristiane Persel
- Department of Medical and Pharmaceutical Sciences, Avenida Tancredo Neves 3224 CEP: 85806-470, Cascavel, Paraná, Brazil
| | - Rinaldo F Gandra
- Department of Medical and Pharmaceutical Sciences, Avenida Tancredo Neves 3224 CEP: 85806-470, Cascavel, Paraná, Brazil
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Kothalawala M, Jayaweera JAAS, Arunan S, Jayathilake A. The emergence of non-albicans candidemia and evaluation of HiChrome Candida differential agar and VITEK2 YST® platform for differentiation of Candida bloodstream isolates in teaching hospital Kandy, Sri Lanka. BMC Microbiol 2019; 19:136. [PMID: 31226938 PMCID: PMC6588897 DOI: 10.1186/s12866-019-1518-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 06/17/2019] [Indexed: 01/28/2023] Open
Abstract
Background Candidemia is an emerging hospital-acquired bloodstream infection (BSI). It is common among severely ill and immunocompromised patients. Even following appropriate therapy in candidemia, recent studies reveal relative high mortality (40%). The global incidence of candidemia shows an incline. In Sri Lanka, candida speciation often difficult where basic facilities are less available. We have compared the risk factors, epidemiology, demography, and performance of HiChrome Candida differential agar (HiCA) characteristics with the VITEK2 YST platform for differentiation of Candida albicans (CA) and non-albicans candida (NAC) from blood culture isolate. Methods This is a laboratory-based cross-sectional study. Positive aerobic BACTEC blood cultures having yeast were identified using HiCA and VITEK2® platform. Epidemiology, risk factors, and clinical outcomes were compared between CA and NAC bloodstream isolates. Results Out of 120 positive yeast samples, VITEK2® has identified 110 (92%) as Candida sp. From that CA-34 (31%) and NAC-76 (69%) were isolated. Candidemia following NCA in neonates (p = 0.02), infants (p = 0.04) and adults (p = 0.02) in ICU and immunocompromised patients were significantly higher. Compared to CA, NAC bacteremia period prevalence (0.00041%) and incidence (0.23 per 100,000-person-years) was significantly high (p = 0.03). NAC 48 (63%) isolates were resistance to azoles. Exposure to antifungals (odds ratio (OR); p = 0.03), prolonged intensive care stay > 14 days (OR-3.3; p = 0.04), having a central venous line for > 8 days (OR-4.3; p = 0.03) and on immunosuppressive treatment (OR-2.4; p = 0.04) was significantly poses risk for NAC candidemia. Sen day mortality was significant among non-albicans cases (p = 0.03) while 30-day mortality was significant among albicans cases (p = 0.04). Compared to VITEK2®, the HiCA method was 93% sensitive and 93% specific in detecting CA. Conclusion Compared to CA, candidemia following NAC was high. NAC isolates were having a high percentage of fluconazole and voriconazole resistance. VITEK2 YST® platform provides antifungal susceptibility with minimal inhibitory concentration (MIC). Impact, this would highlight the use of rapid candida identification flat form with MIC to direct appropriate antifungals for candidemia. For that implementation of novel diagnostic facilities like the VITEK2 YST platform at a tertiary care facility is demanding.
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Affiliation(s)
- Mahen Kothalawala
- Department of Microbiology, Teaching Hospital Kandy Sri Lanka, Kandy, Sri Lanka
| | - J A A S Jayaweera
- Faculty of Medicine and Allied Sciences, Rajarata University of Sri Lanka, Saliyapura, Sri Lanka.
| | - Sinnapoo Arunan
- Department of Microbiology, Teaching Hospital Kandy Sri Lanka, Kandy, Sri Lanka
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Different Metabolic Pathways Are Involved in Response of Saccharomyces cerevisiae to L-A and M Viruses. Toxins (Basel) 2017; 9:toxins9080233. [PMID: 28757599 PMCID: PMC5577567 DOI: 10.3390/toxins9080233] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 07/17/2017] [Accepted: 07/21/2017] [Indexed: 12/11/2022] Open
Abstract
Competitive and naturally occurring yeast killer phenotype is governed by coinfection with dsRNA viruses. Long-term relationship between the host cell and viruses appear to be beneficial and co-adaptive; however, the impact of viral dsRNA on the host gene expression has barely been investigated. Here, we determined the transcriptomic profiles of the host Saccharomyces cerevisiae upon the loss of the M-2 dsRNA alone and the M-2 along with the L-A-lus dsRNAs. We provide a comprehensive study based on the high-throughput RNA-Seq data, Gene Ontology and the analysis of the interaction networks. We identified 486 genes differentially expressed after curing yeast cells of the M-2 dsRNA and 715 genes affected by the elimination of both M-2 and L-A-lus dsRNAs. We report that most of the transcriptional responses induced by viral dsRNAs are moderate. Differently expressed genes are related to ribosome biogenesis, mitochondrial functions, stress response, biosynthesis of lipids and amino acids. Our study also provided insight into the virus–host and virus–virus interplays.
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7
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Industrial Production and Applications of Yeast and Yeast Products. Ind Biotechnol (New Rochelle N Y) 2016. [DOI: 10.1201/b19347-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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8
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Robledo-Leal E, Elizondo-Zertuche M, Villarreal-Treviño L, Treviño-Rangel RDJ, García-Maldonado N, Adame-Rodríguez JM, González GM. Killer behavior within the Candida parapsilosis complex. Folia Microbiol (Praha) 2014; 59:503-6. [DOI: 10.1007/s12223-014-0327-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 05/25/2014] [Indexed: 11/28/2022]
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9
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Cappelli A, Ulissi U, Valzano M, Damiani C, Epis S, Gabrielli MG, Conti S, Polonelli L, Bandi C, Favia G, Ricci I. A Wickerhamomyces anomalus killer strain in the malaria vector Anopheles stephensi. PLoS One 2014; 9:e95988. [PMID: 24788884 PMCID: PMC4006841 DOI: 10.1371/journal.pone.0095988] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Accepted: 04/02/2014] [Indexed: 11/18/2022] Open
Abstract
The yeast Wickerhamomyces anomalus has been investigated for several years for its wide biotechnological potential, especially for applications in the food industry. Specifically, the antimicrobial activity of this yeast, associated with the production of Killer Toxins (KTs), has attracted a great deal of attention. The strains of W. anomalus able to produce KTs, called “killer” yeasts, have been shown to be highly competitive in the environment. Different W. anomalus strains have been isolated from diverse habitats and recently even from insects. In the malaria mosquito vector Anopheles stephensi these yeasts have been detected in the midgut and gonads. Here we show that the strain of W. anomalus isolated from An. stephensi, namely WaF17.12, is a killer yeast able to produce a KT in a cell-free medium (in vitro) as well as in the mosquito body (in vivo). We showed a constant production of WaF17.12-KT over time, after stimulation of toxin secretion in yeast cultures and reintroduction of the activated cells into the mosquito through the diet. Furthermore, the antimicrobial activity of WaF17.12-KT has been demonstrated in vitro against sensitive microbes, showing that strain WaF17.12 releases a functional toxin. The mosquito-associated yeast WaF17.12 thus possesses an antimicrobial activity, which makes this yeast worthy of further investigations, in view of its potential as an agent for the symbiotic control of malaria.
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Affiliation(s)
- Alessia Cappelli
- Scuola di Bioscienze e Medicina Veterinaria, Università degli Studi di Camerino, Camerino, Italy
| | - Ulisse Ulissi
- Scuola di Bioscienze e Medicina Veterinaria, Università degli Studi di Camerino, Camerino, Italy
| | - Matteo Valzano
- Scuola di Bioscienze e Medicina Veterinaria, Università degli Studi di Camerino, Camerino, Italy
| | - Claudia Damiani
- Scuola di Bioscienze e Medicina Veterinaria, Università degli Studi di Camerino, Camerino, Italy
| | - Sara Epis
- Dipartimento di Patologia Animale, Igiene e Sanità Pubblica Veterinaria, Università degli Studi di Milano, Milan, Italy
| | | | - Stefania Conti
- Dipartimento di Scienze Biomediche, Biotecnologiche e Traslazionali, Università degli Studi di Parma, Parma, Italy
| | - Luciano Polonelli
- Dipartimento di Scienze Biomediche, Biotecnologiche e Traslazionali, Università degli Studi di Parma, Parma, Italy
| | - Claudio Bandi
- Dipartimento di Patologia Animale, Igiene e Sanità Pubblica Veterinaria, Università degli Studi di Milano, Milan, Italy
| | - Guido Favia
- Scuola di Bioscienze e Medicina Veterinaria, Università degli Studi di Camerino, Camerino, Italy
| | - Irene Ricci
- Scuola di Bioscienze e Medicina Veterinaria, Università degli Studi di Camerino, Camerino, Italy
- * E-mail:
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McBride RC, Boucher N, Park DS, Turner PE, Townsend JP. Yeast response to LA virus indicates coadapted global gene expression during mycoviral infection. FEMS Yeast Res 2013; 13:162-79. [PMID: 23122216 DOI: 10.1111/1567-1364.12019] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Revised: 10/26/2012] [Accepted: 10/29/2012] [Indexed: 11/29/2022] Open
Abstract
Viruses that infect fungi have a ubiquitous distribution and play an important role in structuring fungal communities. Most of these viruses have an unusual life history in that they are propagated exclusively via asexual reproduction or fission of fungal cells. This asexual mode of transmission intimately ties viral reproductive success to that of its fungal host and should select for viruses that have minimal deleterious impact on the fitness of their hosts. Accordingly, viral infections of fungi frequently do not measurably impact fungal growth, and in some instances, increase the fitness of the fungal host. Here we determine the impact of the loss of coinfection by LA virus and the virus-like particle M1 upon global gene expression of the fungal host Saccharomyces cerevisiae and provide evidence supporting the idea that coevolution has selected for viral infection minimally impacting host gene expression.
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Affiliation(s)
- Robert C McBride
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06520, USA
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Maturano YP, Nally MC, Toro ME, Castellanos de Figueroa LI, Combina M, Vazquez F. Monitoring of killer yeast populations in mixed cultures: influence of incubation temperature of microvinifications samples. World J Microbiol Biotechnol 2012; 28:3135-42. [PMID: 22806751 DOI: 10.1007/s11274-012-1123-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Accepted: 06/30/2012] [Indexed: 10/28/2022]
Abstract
Killer yeasts are frequently used to combat and prevent contamination by wild-type yeasts during wine production and they can even dominate the wine fermentation. Stuck and sluggish fermentations can be caused by an unbalanced ratio of killer to sensitive yeasts in the bioreactor, and therefore it is important to determine the proportion of both populations. The aim of this study was to provide a simple tool to monitor killer yeast populations during controlled mixed microvinifications of killer and sensitive Saccharomyces cerevisiae. Samples were periodically extracted during vinification, seeded on Petri dishes and incubated at 25 and 37 °C; the latter temperature was assayed for possible inactivation of killer toxin production. Colonies developed under the described conditions were randomly transferred to killer phenotype detection medium. Significant differences in the killer/sensitive ratio were observed between both incubation temperatures in all microvinifications. These results suggest that 37 °C seems a better option to determine the biomass of sensitive yeasts, in order to avoid underestimation of sensitive cells in the presence of killer yeasts during fermentations. Incubation at a toxin-inhibiting temperature clearly showed the real ratio of killer to sensitive cells in fermentation systems.
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12
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Antunes J, Aguiar C. Search for killer phenotypes with potential for biological control. ANN MICROBIOL 2011. [DOI: 10.1007/s13213-011-0256-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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13
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Abstract
Intraspecific differentiation of pathogenic microorganisms is a major need in epidemiological studies concerning the source and spread of infections. This requirement is paramount for those etiologic agents of infectious diseases, which are mainly grouped into one species within the genus, such as Candida albicans. Ideally, laboratory methods for biotyping purposes should be sensitive, reproducible, easy, and economical to perform. In addition, the methods should be flexible in their application to taxonomically unrelated pathogens. We have shown that the toxins produced by a selected panel of killer yeasts, each characterized by a wide spectrum of antimicrobial activity, may be used to discriminate strains belonging to the species of the genus Candida and to other species of eukaryotic and prokaryotic pathogenic microorganisms. The "yeast killer system," which may be sharply increased in sensitivity by addition of further standardized killer yeasts, has proven to be of value in the resolution of many cases of clinical and nosocomial fungal infections. Owing to its reliability, economy, and versatility, this phenotypic system can be used as an alternative biotyping method in laboratories lacking the financial and training resources necessary to perform more sophisticated and expensive molecular approaches.
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14
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Fuentefria AM, Perez LRR, Alves d'Azevedo P, Pazzini F, Schrank A, Vainstein MH, Valente P. Typing of Staphylococcus epidermidis clinical strains by a selected panel of Brazilian killer yeasts. J Basic Microbiol 2008; 48:25-30. [PMID: 18247391 DOI: 10.1002/jobm.200700143] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Discrimination of multi-resistant microorganisms in small clinical microbiology laboratories is frequently based on the biologic profile (biotype) of phenotypic markers, such as antimicrobial susceptibility patterns (antibiograms) and serologic or enzymatic typing, but few use indicative microorganisms. The purpose of this study was to evaluate the power of a panel of selected killer yeasts for differentiating and discriminating clinical isolates of Staphylococcus epidermidis from two care hospitals and clinical microbiology laboratories from the South of Brazil. The short panel of eleven killer yeasts was capable of discriminating 100% of the sensitive strains of S. epidermidis using quantitative data matrix (QDM) and differentiating them from strains of coagulase-positive Staphylococcus. Therefore, this phenotypic methodology proved to be valid as a discriminatory tool when applied to these clinical bacteria strains, besides being simple and feasible for routine use even in microbiological laboratories with minimal resources.
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Affiliation(s)
- Alexandre M Fuentefria
- Programa de Pós-Graduação em Biologia Celular e Molecular, Universidade Federal do Rio Grande do Sul, Brazil
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15
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da Silva S, Calado S, Lucas C, Aguiar C. Unusual properties of the halotolerant yeast Candida nodaensis Killer toxin, CnKT. Microbiol Res 2007; 163:243-51. [PMID: 17761407 DOI: 10.1016/j.micres.2007.04.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2007] [Revised: 03/22/2007] [Accepted: 04/08/2007] [Indexed: 10/22/2022]
Abstract
CnKT, the Killer toxin from the extreme halotolerant yeast Candida nodaensis, presents a strong salt-stimulated phenotype and is a resilient toxin, able to cope with very diverse and aggressive environmental conditions. This zymocin is active in a broad range of pH and temperature and tolerates freezing and conservation for long periods of time. CnKT stability is increased under very high ionic strength and its activity is stimulated by sodium ions, which might interfere in the zymocin structure/stability. All these characteristics make CnKT a promising candidate for several biotechnological applications, e.g. in the high-salt food products preservation from spoilage by other yeasts.
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Affiliation(s)
- Sónia da Silva
- Centro de Biologia (CB-UM)/Departamento de Biologia, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal
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Buzzini P, Turchetti B, Vaughan-Martini AE. The use of killer sensitivity patterns for biotyping yeast strains: the state of the art, potentialities and limitations. FEMS Yeast Res 2007; 7:749-60. [PMID: 17425671 DOI: 10.1111/j.1567-1364.2007.00238.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
In recent years molecular techniques have been the most useful tools for the unequivocal identification of undetermined strains at the species level. In many instances, however, a further discrimination at the strain level (biotyping) is required, such as during epidemiological investigations, in which the distribution of pathogenic microorganisms is studied, and for patent protection purposes. Although molecular methods are routinely used also for yeast biotyping, several nonmolecular techniques have been proposed. One of these, the determination of the killer sensitivity pattern (KSP) towards a panel of selected killer toxins has proven to be a good auxiliary method. Despite the plethora of studies published, the potential and limitations of the determination of KSPs have never been critically evaluated. In this review the use of this nonmolecular technique as a biotyping tool is discussed and compared with some currently used DNA-based procedures. In addition, methodological, mechanistic and ecological implications are evaluated.
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Affiliation(s)
- Pietro Buzzini
- Dipartimento di Biologia Vegetale e Biotecnologie Agroambientali, Sezione di Microbiologia Applicata, University of Perugia, Perugia, Italy.
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Fuentefria AM, Franskoviaki IM, Mercado LW, Ramos JP, Vainstein MH, Valente P. Inhibition of clinical and environmental Cryptococcus neoformans isolates by two Brazilian killer yeasts. J Basic Microbiol 2006; 46:87-93. [PMID: 16598831 DOI: 10.1002/jobm.200510018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Two killer yeast strains (HB55 and HB88) capable of inhibiting human pathogenic fungi were isolated from leaves of Hibiscus rosa-sinensis in Brazil. These isolates were identified by conventional methods and sequencing of the D1/D2 region of the 26S rDNA as Kodamaea ohmeri. They inhibited all Cryptococcus neoformans (vars. neoformans, grubii and gattii) strains tested, including reference, clinical and environmental isolates. The killer phenotype was not cured by thermal treatment.
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Buzzini P, Corazzi L, Turchetti B, Buratta M, Martini A. Characterization of the in vitro antimycotic activity of a novel killer protein from Williopsis saturnusDBVPG 4561 against emerging pathogenic yeasts. FEMS Microbiol Lett 2004. [DOI: 10.1111/j.1574-6968.2004.tb09777.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Buzzini P, Berardinelli S, Turchetti B, Cardinali G, Martini A. Fingerprinting of Yeasts at the Strain Level by Differential Sensitivity Responses to a Panel of Selected Killer Toxins. Syst Appl Microbiol 2003; 26:466-70. [PMID: 14529190 DOI: 10.1078/072320203322497509] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We used differential sensitivities to a panel of twenty-five cell-free crude killer toxins to fingerprint forty-four Saccharomyces cerevisiae strains of different origin and all taxonomically certified by nDNA-nDNA reassociation. Cluster analysis of numerical data obtained by different growth inhibition areas observed in Petri dishes allowed the complete and reproducible discrimination of all S. cerevisiae strains.
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Affiliation(s)
- P Buzzini
- Dipartimento di Biologia Vegetale e Biotecnologie Agroambientali, Sezione di Microbiologia Applicata, Università degli Studi di Perugia, Borgo XX Giugno, Perugia, Italy.
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Abstract
Since the initial discovery of the yeast killer system almost 40 years ago, intensive studies have substantially strengthened our knowledge in many areas of biology and provided deeper insights into basic aspects of eukaryotic cell biology as well as into virus-host cell interactions and general yeast virology. Analysis of killer toxin structure, synthesis and secretion has fostered understanding of essential cellular mechanisms such as post-translational prepro-protein processing in the secretory pathway. Furthermore, investigation of the receptor-mediated mode of toxin action proved to be an effective means for dissecting the molecular structure and in vivo assembly of yeast and fungal cell walls, providing important insights relevant to combating infections by human pathogenic yeasts. Besides their general importance in understanding eukaryotic cell biology, killer yeasts, killer toxins and killer viruses are also becoming increasingly interesting with respect to possible applications in biomedicine and gene technology. This review will try to address all these aspects.
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Affiliation(s)
- Manfred J Schmitt
- Angewandte Molekularbiologie (FR 8.3 -- Mikrobiologie), Universität des Saarlandes, Im Stadtwald, Gebäude 2, D-66123 Saarbrücken, Germany.
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Current awareness on yeast. Yeast 2002; 19:185-92. [PMID: 11788972 DOI: 10.1002/yea.820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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