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1.
J Fungi (Basel) ; 10(3)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38535195

RESUMO

Kodamaea ohmeri is an environmental yeast considered a rare emerging pathogen. In clinical settings, the correct identification of this yeast is relevant because some isolates are associated with resistance to antifungals. There is a lack of available data regarding the geographical distribution, virulence, and drug resistance profile of K. ohmeri. To contribute to the knowledge of this yeast, this study aimed to describe in depth three isolates of K. ohmeri associated with fungemia in Honduras. The identification of the isolates was carried out by sequencing the ribosomal ITS region. In addition, the susceptibility profile to antifungals was determined, and some properties associated with virulence were evaluated (exoenzyme production, biofilm formation, cell adhesion, and invasion). The isolates showed strong protease, phospholipase, and hemolysin activity, in addition to being biofilm producers. Adherence and invasion capacity were evident in the HeLa and Raw 264.7 cell lines, respectively. This study expands the understanding of the underlying biological traits associated with virulence in K. ohmeri, and it is the first report of the detection and identification of K. ohmeri in Honduras as a cause of human infection.

2.
Exp Ther Med ; 27(1): 43, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38125361

RESUMO

Kodamaea ohmeri (K. ohmeri) is an ascosporogenic species of yeast that belongs to the genus Ascosporogenous and the family of Saccharomycetaceae. It has recently been found to cause various types of infections, particularly in critically ill immunocompromised patients. The present study describes a case of hospital-acquired pneumonia caused by K. ohmeri during veno-arterial extracorporeal membrane oxygenation. The fungal culture turned negative after the administration of caspofungin and amphotericin B. Extracorporeal membrane oxygenation (ECMO) is an adjunctive medical technique that provides temporary cardiopulmonary support for patients. Previous observations have suggested that the immune function of patients will typically decline during the use of ECMO, rendering infection to be one of the main complications of ECMO. K. ohmeri is a rare pathogenic fungus, particularly in immunocompromised individuals with vascular catheters, while amphotericin B is the most common antifungal therapy administered to treat K. ohmeri infections. It is important to raise awareness of rare fungal infections and actively treat them.

3.
Infect Genet Evol ; 117: 105547, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38159712

RESUMO

Kodamaea ohmeri, an emerging human pathogen, caused both sporadic and nosocomial infections among immunocompromised people with high mortality. However, there is limited research on the molecular epidemiology of K. ohmeri. A total of fifty microsatellite loci were designed based on K. ohmeri type strain NRRL Y-1932 and three loci were finally selected for microsatellite analysis. Non-duplicated K. ohmeri isolates and strains of other species were collected across China as a part of CHIF-NET program for sensitivity and specificity verification. Antifungal susceptibility was determined using Sensititre YeastOne TM YO10. The three loci (P10, P11 and P26), with a cumulative discriminatory power of 0.98, exhibited a prospective specificity and reproducibility in the PCR of 92 K. ohmeri strains from different hospitals. A total of 54 microsatellite types (MT) were identified and most of them distributed sporadically. However, six strains of MT12 clustered in HZ hospital and were isolated in the same department within two months, indicating a potential outbreak. Of seven isolates exhibited MIC values of >8 mg/L for fluconazole, three isolates from LR hospital shared the same genotype of MT44. Herein, we established a set of microsatellite loci for K. ohmeri, as a rapid and specific tool for genotyping K. ohmeri, and identified several potential clusters. This study will help us better understand the molecular epidemiology of the emerging pathogen K. ohmeri.


Assuntos
Antifúngicos , Saccharomycetales , Humanos , Genótipo , Estudos Prospectivos , Reprodutibilidade dos Testes , Antifúngicos/uso terapêutico
4.
J Fungi (Basel) ; 9(6)2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37367594

RESUMO

Candida auris, Candida blankii, and Kodamaea ohmeri have been regarded as emerging fungal pathogens that can cause infections with high mortality. For genotyping of C. auris, a multilocus sequence typing (MLST) scheme based on four locus sequences has been reported, while there is no typing scheme for C. blankii and K. ohmeri. In the present study, the existing MLST scheme of C. auris was modified by adding more locus types deduced from sequence data available in the GenBank database. Furthermore, MLST schemes of C. blankii and K. ohmeri were developed using the four cognate loci (ITS, RPB1, RPB2, D1/D2) and similar sequence regions to those of C. auris. These MLST schemes were applied to identify the ST (sequence type) of clinical isolates of C. auris (n = 7), C. blankii (n = 9), and K. ohmeri (n = 6), derived from septicemia or otomycosis in Bangladesh in 2021. All the C. auris isolates were classified into a single ST (ST5) and clade I, having a Y132F substitution in ERG11p, which is associated with azole resistance. Similarly, all the C. blankii isolates belonged to a single type (ST1). In contrast, six K. ohmeri isolates were assigned to five types (ST1-ST5), suggesting its higher genetic diversity. These findings revealed the availability of MLST schemes for these three fungal species for understanding their clonal diversity among clinical isolates.

5.
BMC Infect Dis ; 22(1): 903, 2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36460998

RESUMO

BACKGROUND: Kodamaea ohmeri is a rare pathogen with high mortality and is found among blood samples in a considerable proportion; however, gastrointestinal infection of K. ohmeri is extremely rare. Invasive pulmonary aspergillosis is also an uncommon fungal; these two fungal infections reported concomitantly are unprecedented. CASE PRESENTATION: We described a case of a 37-year-old male who got infected with K. ohmeri and invasive pulmonary aspergillosis. We used the mass spectrometry and histopathology to identify these two fungal infections separately. For the treatment of K. ohmeri, we chose caspofungin. As for invasive pulmonary aspergillosis, we used voriconazole, amphotericin B, and then surgery. The patient was treated successfully through the collaboration of multiple disciplines. CONCLUSIONS: We speculate that the destruction of the intestinal mucosa barrier can make the intestine one of the ways for certain fungi to infect the human body.


Assuntos
Fungemia , Aspergilose Pulmonar Invasiva , Saccharomycetales , Adulto , Humanos , Masculino , Caspofungina/uso terapêutico , Fungemia/microbiologia , Aspergilose Pulmonar Invasiva/diagnóstico , Aspergilose Pulmonar Invasiva/tratamento farmacológico
6.
World J Microbiol Biotechnol ; 38(12): 244, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36280608

RESUMO

The prevalence of opportunistic human fungal pathogens is increasing worldwide, and antimicrobial resistance is one of the greatest medical challenges the world faces. Therefore, this study aimed to develop a novel agent to control fungal pathogens. The honeybee products (honey, royal jelly, propolis, bee bread, and bee venom) were screened against unicellular fungal (UCF) pathogens (Cryptococcus neoformans, Kodamaea ohmeri, and Candida albicans) and the bee venom was only exhibited an inhibitory effect against them. The protein contents of crude bee venom were separated using the gel filtration technique into eight fractions which were visualized on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to confirm the presence of five bands with molecular weights of 65, 43, 21, 15, and 3 KDa. Bee venom (BV) of Apis mellifera loaded chitosan nanoparticles were prepared by the ionotropic gelation method. The encapsulation efficiency%, average size, zeta potentials, and surface appearance by Transmission electron microscope (TEM) were evaluated for the prepared nanoparticles. The minimum inhibitory concentration (MIC) of crude BV and BV loaded chitosan nanoparticles (BV-CNPs) was evaluated against the offer mentioned UCF where the MIC values of crude BV were 6.25, 3.12 & 6.25 while MIC values in the case of BV-CNPs were decreased to 3.12, 3.12 & 1.56 mg/ml against C. neoformans, K. ohmeri and C. albicans, respectively. Also, the results showed that BV-CNPs suppressed the biofilm formation as well as yeast to hyphal transition formed by the examined UCF. These results revealed that BV-CNPs are a promising natural compound for fungal pathogens treatment.


Assuntos
Venenos de Abelha , Quitosana , Cryptococcus neoformans , Nanopartículas , Própole , Humanos , Animais , Quitosana/farmacologia , Quitosana/metabolismo , Antifúngicos/farmacologia , Venenos de Abelha/farmacologia , Própole/farmacologia , Dodecilsulfato de Sódio/farmacologia , Nanopartículas/metabolismo , Candida albicans , Cryptococcus neoformans/metabolismo , Biofilmes
7.
Trop Med Infect Dis ; 7(9)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36136623

RESUMO

Candida species are major fungal pathogens in humans. The aim of this study was to determine the prevalence of individual Candida species and their susceptibility to antifungal drugs among clinical isolates in a tertiary care hospital in Bangladesh. During a 10-month period in 2021, high vaginal swabs (HVSs), blood, and aural swabs were collected from 360 patients. From these specimens, Candida spp. was isolated from cultures on Sabouraud dextrose agar media, and phenotypic and genetic analyses were performed. A total of 109 isolates were recovered, and C. albicans accounted for 37%, being derived mostly from HVSs. Among non-albicans Candida (NAC), C. parapsilosis was the most frequent, followed by C. ciferrii, C. tropicalis, and C. glabrata. Three isolates from blood and two isolates from aural discharge were genetically identified as C. auris and Kodamaea ohmeri, respectively. NAC isolates were more resistant to fluconazole (overall rate, 29%) than C. albicans (10%). Candida isolates from blood showed 95% susceptibility to voriconazole and less susceptibility to fluconazole (67%). Two or three amino acid substitutions were detected in the ERG11 of two fluconazole-resistant C. albicans isolates. The present study is the first to reveal the prevalence of Candida species and their antifungal susceptibility in Bangladesh.

8.
Front Microbiol ; 12: 736582, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34566940

RESUMO

Background: Kodamaea ohmeri, previously known as Pichia ohmeri or Yamadazyma ohmeri, has been regarded as an emerging human pathogen in recent decades, and has caused various types of infections with high mortality. This study systematically reviewed all the published cases of K. ohmeri infection, aiming to have a better understanding of the clinical and epidemiological characteristics of the organism. Methods: All the published literature (as of March 31, 2021) on K. ohmeri, in four databases: PubMed, Embase, Web of Science, and CNKI, were systematically reviewed to select appropriate studies for summarizing the demographic information, clinical and microbiological characteristics of relevant infections. Results: A total of 51 studies involving 67 patients were included for final analysis, including 49 sporadic cases and two clusters of outbreaks. Neonates and the elderly constituted the majority of patients, and fungemia was the dominant infection type. Comorbidities (like malignancy, diabetes, and rheumatism), invasive operations, previous antibiotic use and prematurity, were commonly described in patients. Gene sequencing and broth microdilution method, were the most reliable way for the identification and antifungal susceptibility testing of K. ohmeri, respectively. Amphotericin B and fluconazole were the commonest antifungal therapies administered. The calculated mortality rates for K. ohmeri infection was higher than that of common candidemia. Conclusion: In this study, we systematically reviewed the epidemiology, clinical characteristics, microbiological features, treatment, and outcomes, of all the published cases on K. ohmeri. Early recognition and increased awareness of K. ohmeri as an emerging human pathogen by clinicians and microbiologists is important for effective management of this organism.

9.
EFSA J ; 19(7): e06689, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34257732

RESUMO

The qualified presumption of safety (QPS) approach was developed to provide a regularly updated generic pre-evaluation of the safety of biological agents, intended for addition to food or feed, to support the work of EFSA's Scientific Panels. The QPS approach is based on an assessment of published data for each agent, with respect to its taxonomic identity, the body of relevant knowledge, safety concerns and occurrence of antimicrobial resistance. Safety concerns identified for a taxonomic unit (TU) are, where possible, confirmed at the species/strain or product level and reflected by 'qualifications'. In the period covered by this statement, no new information was found that would change the status of previously recommended QPS TUs. Schizochytrium limacinum, which is a synonym for Aurantiochytrium limacinum, was added to the QPS list. Of the 78 microorganisms notified to EFSA between October 2020 and March 2021, 71 were excluded; 16 filamentous fungi, 1 Dyella spp., 1 Enterococcus faecium, 7 Escherichia coli, 1 Streptomyces spp., 1 Schizochytrium spp. and 44 TUs that had been previously evaluated. Seven TUs were evaluated: Corynebacterium stationis and Kodamaea ohmeri were re-assessed because an update was requested for the current mandate. Anoxybacillus caldiproteolyticus, Bacillus paralicheniformis, Enterobacter hormaechei, Eremothecium ashbyi and Lactococcus garvieae were assessed for the first time. The following TUs were not recommended for QPS status: A. caldiproteolyticus due to the lack of a body of knowledge in relation to its use in the food or feed chain, E. hormaechei, L. garvieae and K. ohmeri due to their pathogenic potential, E. ashbyi and C. stationis due to a lack of body of knowledge on their occurrence in the food and feed chain and to their pathogenic potential. B. paralicheniformis was recommended for the QPS status with the qualification 'absence of toxigenic activity' and 'absence of genetic information to synthesize bacitracin'.

10.
Indian J Med Microbiol ; 39(2): 252-255, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33966863

RESUMO

A 46-year-old male was having un-resolving fever for six weeks. Trans-esophageal echocardiography showed tricuspid valve myxoma (TVM). Kodamaea ohmeri was identified in 2 blood cultures and confirmed by 28S rDNA sequencing. Over three weeks of liposomal Amphotericin-B, fever has subsided thus indicated a clinical response. Subsequent echocardiography revealed no regression of suspected vegetation, and it was removed, and TV replacement was done. Histopathology revealed an infected myxoma and K. omeri was detected following 28S rDNA sequencing. For cardiac myxoma, excision is offered while for IE prolonged use of antifungals with or without vegetectomy is offered. So proper identification is important.


Assuntos
Fungemia , Mixoma , Saccharomycetales/patogenicidade , Valva Tricúspide/microbiologia , DNA Ribossômico/genética , Fungemia/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Mixoma/diagnóstico , Mixoma/microbiologia
11.
Germs ; 11(4): 614-616, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35096680

RESUMO

INTRODUCTION: Kodamaea ohmeri, a yeast frequently mistaken for Candida, has emerged in recent years as an opportunistic fungal pathogen, showing a predilection towards patients with immunosuppression, or those with long-term central venous access. This report describes a central line associated bloodstream infection (CLABSI) due to K. ohmeri, in a young child, which was successfully treated. CASE REPORT: The patient is a 5-year-old male with a history of short gut syndrome, and total parenteral nutrition (TPN) dependence who presented to the emergency room with a two-day history of productive-cough, rhinorrhea, and fever. Antibiotic therapy was initiated with cefepime and vancomycin for suspected CLABSI. However, within the first twenty-four hours of his admission, his initial blood culture from his central venous catheter became positive for yeast so fluconazole was added due to suspicion of candidemia. During his admission, his initial central line and peripheral blood culture were later speciated as Kodamaea ohmeri, with susceptibilities to fluconazole (MIC: 4 µg/mL) and micafungin (MIC: 0.125 µg/mL). After evaluating the susceptibilities, he was transitioned to micafungin. CONCLUSIONS: This case report further acknowledges that while rare, K. ohmeri is an emerging pathogen that has the potential to be life threatening if not accurately identified and treated with the optimal, empiric antifungal therapy. Due to potentially high mortality and antifungal resistance, this yeast species should be on the differential in patients that present with a central venous catheter and/or other underlying risk factors. Favorable outcomes can be achieved by removing indwelling catheters and administering optimal antifungal therapy.

12.
EFSA J ; 18(2): e05965, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32874211

RESUMO

Qualified presumption of safety (QPS) was developed to provide a generic safety evaluation for biological agents to support EFSA's Scientific Panels. The taxonomic identity, body of knowledge, safety concerns and antimicrobial resistance are assessed. Safety concerns identified for a taxonomic unit (TU) are where possible to be confirmed at strain or product level, reflected by 'qualifications'. No new information was found that would change the previously recommended QPS TUs and their qualifications. The list of microorganisms notified to EFSA was updated with 54 biological agents, received between April and September 2019; 23 already had QPS status, 14 were excluded from the QPS exercise (7 filamentous fungi, 6 Escherichia coli, Sphingomonas paucimobilis which was already evaluated). Seventeen, corresponding to 16 TUs, were evaluated for possible QPS status, fourteen of these for the first time, and Protaminobacter rubrum, evaluated previously, was excluded because it is not a valid species. Eight TUs are recommended for QPS status. Lactobacillus parafarraginis and Zygosaccharomyces rouxii are recommended to be included in the QPS list. Parageobacillus thermoglucosidasius and Paenibacillus illinoisensis can be recommended for the QPS list with the qualification 'for production purposes only' and absence of toxigenic potential. Bacillus velezensis can be recommended for the QPS list with the qualification 'absence of toxigenic potential and the absence of aminoglycoside production ability'. Cupriavidus necator, Aurantiochytrium limacinum and Tetraselmis chuii can be recommended for the QPS list with the qualification 'production purposes only'. Pantoea ananatis is not recommended for the QPS list due to lack of body of knowledge in relation to its pathogenicity potential for plants. Corynebacterium stationis, Hamamotoa singularis, Rhodococcus aetherivorans and Rhodococcus ruber cannot be recommended for the QPS list due to lack of body of knowledge. Kodamaea ohmeri cannot be recommended for the QPS list due to safety concerns.

13.
Australas J Dermatol ; 61(2): e213-e216, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31880812

RESUMO

We present a case of subcutaneous granuloma caused by Kodamaea ohmeri and describe the histopathological characteristics and skin lesions caused by this pathogen. A 55-year-old woman, with a history of rheumatoid arthritis, presented with red, painless plaque on her forehead, persistent for 3 months; based on the histopathological and mycological findings and gene sequencing, the patient was diagnosed with subcutaneous granuloma caused by K. ohmeri. This report highlights that early identification and diagnosis and optimal regimens are vital in the management of this intractable infection.


Assuntos
Granuloma Anular/diagnóstico , Hospedeiro Imunocomprometido , Saccharomycetales/isolamento & purificação , Antifúngicos/uso terapêutico , Artrite Reumatoide/complicações , Feminino , Granuloma Anular/tratamento farmacológico , Humanos , Pessoa de Meia-Idade
14.
J Basic Microbiol ; 59(8): 792-806, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31368594

RESUMO

The aim of this study was to examine four strains of two yeast species in relation to their capability for assimilating alkanes in the presence of heavy metals (HMs). The four strains tested were Candida pseudoglaebosa ENCB-7 and Kodamaea ohmeri ENCB-8R, ENCB-23, and ENCB-VIK. Determination was made of the expression of CYP52 genes involved in alkane hydroxylation. When exposed to Cu2+ , Zn2+ , Pb2+ , Cd2+ , and As3+ at pH 3 and 5, all four strains could assimilate several n-alkanes having at least six carbon atoms. The three K. ohmeri strains could also utilize branched alkanes, cycloalkanes, and n-octanol as sole carbon sources. Kinetic assays demonstrated greater biomass production and specific growth of the yeasts exposed to long-chain n-alkanes. Fragments of paralogous CYP52 genes of C. pseudoglaebosa ENCB-7 and K. ohmeri ENCB-23 were amplified, sequenced, and phylogenetically evaluated. Reverse-transcription polymerase chain reaction revealed that n-nonane and n-decane induced to CpCYP52-G3, CpCYP52-G9, and CpCYP52-G10. KoCYP52-G3 was induced with n-decane and n-octanol. Also, CpCYP52-G3 and CpCYP52-G9 were induced by glucose. In conclusion, C. pseudoglaebosa and K. ohmeri were able to degrade several alkanes in the presence of HMs and under acidic conditions. These yeasts harbor paralogous alkane-induced CYP52 genes, which display different profiles of transcriptional expression.


Assuntos
Alcanos/metabolismo , Metais Pesados/metabolismo , Saccharomycetales/metabolismo , Alcanos/química , Biodegradação Ambiental , Biomassa , Candida/classificação , Candida/genética , Candida/crescimento & desenvolvimento , Candida/metabolismo , Sistema Enzimático do Citocromo P-450/genética , DNA Ribossômico/genética , Proteínas Fúngicas/genética , Concentração de Íons de Hidrogênio , Cinética , Filogenia , Saccharomycetales/classificação , Saccharomycetales/genética , Saccharomycetales/crescimento & desenvolvimento
15.
BMC Infect Dis ; 19(1): 570, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31262263

RESUMO

BACKGROUND: Kodamaea ohmeri is a yeast is frequently mistaken for Candida, which belongs to the same family. This micro-organism has been reported to cause life-threatening infections in humans. CASE PRESENTATION: A 81-year-old woman developed a severe fungemic pulmonary infection due to Kodamaea ohmeri that was identified from bronchoalveolar fluid and blood cultures, which is unusual in immunocompetent patients. Because K. ohmeri was first wrongly identified as Candida albicans, the patient inadequately received caspofungin, which was clinically ineffective, especially as the strain was resistant to echinocandins. Clinical cure was obtained after treatment was switched to voriconazole. CONCLUSIONS: An increasing number of serious infections due to K. ohmeri has been reported in the literature, but the correct identification of this micro-organism remains difficult.


Assuntos
Fungemia/tratamento farmacológico , Fungemia/microbiologia , Saccharomycetales/patogenicidade , Idoso de 80 Anos ou mais , Antifúngicos/uso terapêutico , Candida albicans/patogenicidade , Erros de Diagnóstico , Farmacorresistência Fúngica/efeitos dos fármacos , Equinocandinas/uso terapêutico , Feminino , Humanos , Testes de Sensibilidade Microbiana , Saccharomycetales/efeitos dos fármacos , Voriconazol/uso terapêutico
16.
Infect Drug Resist ; 12: 1657-1664, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354314

RESUMO

BACKGROUND: Kodamaea ohmeri has been a rare fungal pathogen in the past decades but is now becoming more common in various invasive fungal diseases, with high mortality. There are limited data on the occurrence and distribution of K. ohmeri. METHODS: Sixty-two K. ohmeri isolates collected from 24 hospitals in China over a 7-year period were studied. Performance of three phenotypic methods in the identification of this organism was assessed against a gold standard, 26S rDNA sequencing. Original identification results submitted by the participating local hospitals were reviewed. The Sensititre YeastOne YO10 (SYY) was evaluated in determining the in vitro antifungal susceptibilities using standard broth microdilution method (BMD) as a reference, and essential agreement (EA) was calculated. RESULTS: Accurate species identification was achieved in 82.3% and 96.8% of the cases by Vitek 2 Compact and Vitek mass spectrometry (MS), respectively. For Bruker MS, 12.9% and 96.8% of the isolates were correctly identified to species level using the direct transfer and protein extraction methods, respectively. Only 29 (46.8%) isolates were initially correctly identified as K. ohmeri by the local hospitals. The highest misidentification rate (100%, 16/16) was observed in CHROMagar. According to BMD, the highest MIC90 was seen in fluconazole (8 µg/mL), followed by 1 µg/mL for micafungin, caspofungin, 5-fluorocytosine, and amphotericin B, 0.5 µg/mL for itraconazole, 0.25 µg/mL for posaconazole and voriconazole. Significant differences in EAs for different drugs were observed, ranging from 95.2% for amphotericin B to 22.6% for itraconazole between SYY and BMD. CONCLUSION: Our study emphasizes the need for accurate identification of clinical K. ohmeri isolates and the importance of validating antifungal susceptibility by standard BMD.

17.
J Basic Microbiol ; 2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31183881

RESUMO

The aim of this study was to examine four strains of two yeast species in relation to their capability for assimilating alkanes in the presence of heavy metals (HMs). The four strains tested were Candida pseudoglaebosa ENCB-7 and Kodamaea ohmeri ENCB-8R, ENCB-23, and ENCB-VIK. Determination was made of the expression of CYP52 genes involved in alkane hydroxylation. When exposed to Cu2+ , Zn2+ , Pb2+ , Cd2+ , and As3+ at pH 3 and 5, all four strains could assimilate several n-alkanes having at least six carbon atoms. The three K. ohmeri strains could also utilize branched alkanes, cycloalkanes, and n-octanol as sole carbon sources. Kinetic assays demonstrated greater biomass production and specific growth of the yeasts exposed to long-chain n-alkanes. Fragments of paralogous CYP52 genes of C. pseudoglaebosa ENCB-7 and K. ohmeri ENCB-23 were amplified, sequenced, and phylogenetically evaluated. Reverse-transcription polymerase chain reaction revealed that n-nonane and n-decane induced to CpCYP52-G3, CpCYP52-G9, and CpCYP52-G10. KoCYP52-G3 was induced with n-decane and n-octanol. Also, CpCYP52-G3 and CpCYP52-G9 were induced by glucose. In conclusion, C. pseudoglaebosa and K. ohmeri were able to degrade several alkanes in the presence of HMs and under acidic conditions. These yeasts harbor paralogous alkane-induced CYP52 genes, which display different profiles of transcriptional expression.

18.
Microb Pathog ; 132: 282-292, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31082527

RESUMO

Cutaneous fungal infections include onychomycosis, an infection of the nail that affects both healthy and immunocompromised patients. This study investigated the in vitro hydrolytic enzymes production, adhesion and biofilm formation capacity of Candida parapsilosis complex species and Kodamaea ohmeri isolates from onychomycoses of HIV/AIDS patients and also established the antifungal sensitivity profiles of these isolates. Onychomycosis in HIV/AIDS patients showed a high prevalence of emerging yeasts, among which C. parapsilosis complex species and K. ohmeri were the most frequent. Three C. parapsilosis sensu stricto and two C. orthopsilosis isolates were resistant to amphotericin B and 83% of isolates were resistant to terbinafine. All three different species evaluated were proteinase and hemolysin producers. All isolates adhered to stainless steel and siliconized latex surfaces, and carbohydrates intensified adhesion of all isolates. Isolates adhered to keratinous nail and 50% formed biofilms with strong intensity. In multispecies or polymicrobial biofilms, C. albicans and Staphylococcus aureus regulated the biofilm formation of the analyzed species, decreasing the number of their cells in biofilms. The isolation of emerging yeast species from onychomycosis which are great producers of hydrolytic enzymes and with high adhesion and biofilm formation capacity is a result that should be considered relevant in clinical practice. In addition, half of the isolates was resistant to at least one of the tested antifungals. Taken together these data corroborate the infectious capacity and viability of these isolates under favorable conditions.


Assuntos
Síndrome de Imunodeficiência Adquirida/complicações , Candida parapsilosis/isolamento & purificação , Onicomicose/microbiologia , Saccharomycetales/isolamento & purificação , Adulto , Anfotericina B/farmacologia , Antifúngicos/farmacologia , Biofilmes/crescimento & desenvolvimento , Candida parapsilosis/efeitos dos fármacos , DNA Fúngico , Farmacorresistência Fúngica , Feminino , HIV , Humanos , Látex , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Onicomicose/epidemiologia , Saccharomycetales/efeitos dos fármacos , Aço Inoxidável , Terbinafina/farmacologia , Virulência , Adulto Jovem
19.
Infect Prev Pract ; 1(1): 100006, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-34368672

RESUMO

Kodamaea ohmeri is a rare yeast pathogen that has recently emerged as an important cause of fungaemia in immunocompromised patients. In most cases, identification to the species level requires the adoption of new tools, including matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) or DNA sequencing. As K. ohmeri is a teleomorph of Candida guilliermondii var. membranaefaciens and its susceptibility to fluconazole is variable, a rapid and accurate identification of this yeast is important. Echinocandins may be the first choice for empiric therapy for this pathogen. We report the case of a 25-year-old male patient from North China who developed a catheter-related bloodstream infection caused by K. ohmeri. He was treated with caspofungin in hospital. He improved after removal of the central venous catheter and use of caspofungin as therapy. The K. ohmeri strain was identified using a MALDI-TOF mass spectrometer and a Vitek 2YST card. Definitive identification was obtained by a sequencing test of the internal transcribed spacer regions of the rDNA. Our patient findings, the first reported in mainland China, highlighted the diagnostic challenges associated with catheter-related bloodstream infection caused by fungi.

20.
Med Mycol Case Rep ; 22: 21-23, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30094134

RESUMO

Kodamaea ohmeri is a relatively rare yeast isolated form clinical specimens, and it is known to be a causative fungus of severe invasive infectious diseases in immunocompromised hosts. Herein, we describe fungemia due to K. ohmeri in a patient with a severe extended burn. The isolate was obtained from not only blood specimens but also skin lesions. We should be aware of risk for fungemia including K. ohmeri in case of severe burn.

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