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A hospital-based cross-sectional study was conducted during 2018-2019 to decipher the prevalence of yeast mastitis. The results indicated a 19.68% prevalence of clinical mastitis in bovines. Among them, 5.51% of samples revealed yeasts constituting 1.09% overall prevalence. Candida albicans was recorded as a significant fungal agent involved in clinical bovine mastitis. We record the association of Kodamaea ohmeri in clinical bovine mastitis. On proteomic and molecular confirmation, K. ohmeri isolates were re-identified from phenotypically identified Candida isolates associated with bovine mastitis. After conventional identification, the yeast isolates were re-identified by MALDI-TOF MS-based proteomic approaches. The D1/D2 domains of 26S-rRNA gene and 5.8S-internal transcribed spacer (ITS) rDNA regions based molecular phylogenetic analysis identified the isolates as K. ohmeri. The isolates were resistant to fluconazole. This study reports the first systemic study of K. ohmeri isolates recovered from bovine clinical mastitis, utilizing conventional, automated, proteomic, and genomic approaches followed by antifungal susceptibility. The findings suggest K. ohmeri as a potent opportunistic emerging pathogen of veterinary and public health concern, need for accurate identification of fungal agents from mycotic mastitis, and use of validated antifungal susceptibility assay because of developing resistance to antimycotic agents. Our findings suggest judicious use of fluconazole and alternative antifungal agents may be considered in case of an outbreak.

Introduction Species of genus Candida are part of the common microbiota of humans; however, some of the Candida species are known opportunistic pathogens. Formation of biofilms, resistance to antifungal drugs, and increase in asymptomatic infections demands more studies on isolation, identification and characterization of Candida from clinical samples. Methods The present manuscript deals with assessment of authentic yeast identification by three methods viz., DNA sequencing of 28S rRNA gene, protein profiles using MALDI-TOF MS, and colony coloration on chromogenic media. Antifungal susceptibility and in vitro cell invasion assays were performed to further characterize these isolates. Results Comparison of three methods showed that DNA sequence analysis correctly identified more than 99.4% of the isolates up to species level as compared to 89% by MALDI-TOF MS. In this study, we isolated a total of 176 yeasts from clinical samples and preliminary morphological characters indicated that these yeast isolates belong to the genus Candida. The species distribution of isolates was as follows: 75 isolates of Candida albicans (42.61%), 50 of C. tropicalis (28.40%), 22 of C. glabrata (12.5%), 14 of C. parapsilosis (7.95%) and 4 of Clavispora lusitaniae (2.27%). Other species like Cyberlindnera fabianii, Issatchenkia orientalis, Kluyveromyces marxianus, Kodamaea ohmeri, Lodderomyces sp., and Trichosporon asahii were less than 2%. Antifungal susceptibility assay performed with 157 isolates showed that most of the isolates were resistant to the four azoles viz., clotrimazole, fluconazole, itraconazole, and ketoconazole, and the frequency of resistance was more in non-albicans Candida isolates. The susceptibility to azole drugs ranged from 7% to 48%, while 75% of the tested yeasts were susceptible to nystatin. Moreover, 88 isolates were also tested for their capacity to invade human cells using HeLa cells. In vitro invasion assay showed that most of the C. albicans isolates showed epithelial cell invasion as compared to isolates belonging to C. glabrata, C. parapsilosis and C. tropicalis. Discussion The identification of yeasts of clinical origin by sequencing of 28S rRNA gene performed better than MALDI-TOF MS. The present study reiterates the world scenario wherein there is a shift from Candida strains to emerging opportunistic pathogens which were earlier regarded as environmental strains. The present study enlightens the current understanding of identification methods for clinical yeast isolates, increased antifungal drug resistance, epithelial cell invasion as a virulence factor, and diversity of yeasts in Indian clinical samples.

The study aimed to investigate yeast communities in sugarcane (Saccharum officinarum Linn.) phylloplane in Thailand by a culture-dependent approach using a direct isolation method; namely, plating of leaf washing for yeast isolation. A total of 150 yeast strains were obtained from 79 sugarcane leaf samples collected in ten provinces. Identification on the basis of the D1/D2 region of the large subunit (LSU) rRNA gene sequence analysis revealed that 126 yeast strains (84%) were identified to be yeast in the phylum Basidiomycota and 24 strains (16%) were in the phylum Ascomycota. Basidiomycetous yeast consisted of 27 known species in 18 genera viz. Cystobasidium, Dioszegia, Dirkmeia, Hannaella, Jaminaea, Kwoniella, Langdonia, Moesziomyces, Occultifur, Papiliotrema, Piskurozyma, Pseudozyma, Rhodosporidiobolus, Rhodotorula, Saitozyma, Sporobolomyces, Symmetrospora and Tremella, whereas, ascomycetous yeast consisted of three species viz. Candida parapsilosis, Kodamaea ohmeri and Meyerozyma caribbica. In addition, the most common known yeast species detected were Dirkmeia churashimaensis with relative frequency and frequency of occurrence of 12.0 and 22.8%, respectively. Subsequently, seven strains were found to be five new yeast species, which were already proposed as Kalmanozyma vetiver, Wickerhamiella siamensis, Papiliotrema siamense, Hannaella phyllophila and Occultifur tropicalis. The results of this study revealed a higher number of yeast strains and species in the phylum Basidiomycota, which agreed with other reports. However, the present results are opposite to those of our previous study when the enrichment technique was used for yeast isolation.

Background and purpose Opportunistic fungal infections have been on a growing trend since the last two decades. Among the opportunistic fungal agents, Candida species, Cryptococcus neoformans, and Aspergillus fumigatus account for most of the life-threatening infections in immunocompromised individuals. Regarding this, the present study aimed to investigate the molecular identification and antifungal susceptibility pattern of Candida species isolated from HIV-infected patients. Materials and methods This study was conducted on 80 clinical samples collected from HIV-infected patients with suspected candidiasis referring to Tagore Medical College and Hospital, Rathinamangalam and Government Hospital of Thoracic Medicine, in Chennai, India, for 18 months (i.e., May 2016-December 2017). Phenotypic and molecular identification was accomplished using internal transcribed spacer region 1 (ITS1) and ITS4 primers. The antifungal susceptibility pattern of the isolates against four antifungal agents was also determined by both disk diffusion and broth dilution methods. Results In the present study, the prevalence of candidiasis was obtained as 75% (n=60). Candida tropicalis was the predominant identified species. All the emerging species (i.e., Kodamaea ohmeri, Hanseniaspora opuntiae, and C. orthopsilosis) were identified through molecular identification since the phenotypic identification was inconclusive. In terms of the susceptibility pattern, 63.3% and 18.3% of the isolates were resistant to fluconazole and voriconazole, respectively. Candida albicans was also found to be resistant to amphotericin B. Conclusion Molecular assay led to the identification of K. ohmeri, H. opuntiae, and C. orthopsilosis, which were multidrug-resistant. This study highlighted the need for the prompt and timely identification of clinical yeast isolates given the emergence of many rare species and their capability of causing life-threatening infections and outbreaks. In the laboratories where molecular diagnostic methods are not available, alternative services of reference laboratories can be utilized as cost-effective measures. With regard to the growing prevalence of antifungal drug resistance, antifungal susceptibility testing should be made mandatory for effective patient management.

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’. info:eu-repo/semantics/publishedVersion

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 qualifications; the absence of toxigenic potential and the absence of aminoglycoside production, including the genes encoding this. Cupriavidus necator, Aurantiochytrium limacinum and Tetraselmis chuii can be recommended for the QPS list with the qualification; for 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.

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. Keywords: Kodamaea ohmeri, Echinocandin, Fungemia, Microbial substitution

This work aimed to evaluate in vitro antagonistic activities and mechanisms of endophytic yeasts against phytopathogenic fungi. A total of 407 yeast strains isolated from tissue of rice, corn, and sugarcane leaves were evaluated for their antagonistic activities against ten phytopathogenic fungi. Only strains of Wickerhamomyces anomalus and Kodamaea ohmeri were found to inhibit the growth of phytopathogenic fungi. Wickerhamomyces anomalus (seven strains) showed antagonistic activity against Curvularia lunata (cause of dirty panicle disease of rice), three Fusarium moniliforme strains (cause of bakanae disease of rice, stalk rot disease of corn, and red rot disease of sugarcane), and Rhizoctonia solani (cause of sheath blight disease of rice). Whereas four Kodamae ohmeri strains inhibited growth of F. moniliforme (cause of bakanae disease of rice). Antagonistic mechanisms of W. anomalus were based on the production of volatile organic compounds (VOCs) (mainly 3-methyl-1-butyl acetate and 3-methyl-1-butanol), fungal cell wall-degrading enzymes (β-1,3-glucanase and chitinase), and siderophores as well as phosphate and zinc oxide solubilization. As for K. ohmeri, the production of VOCs (mainly 3-methyl-1-butanol), β-1,3-glucanase and chitinase were hypothesized as possible mechanisms. The antagonistic activity of W. anomalus against these phytopathogenic fungi and of K. ohmeri against F. moniliforme, and the analysis of the VOCs produced by K. ohmeri are reported for the first time. Two W. anomalus strains, DMKU-RE13 and DMKU-CE52, were evaluated for controlling rice sheath blight disease caused by R. solani in rice plants in the greenhouse and found to suppress the disease 55.2-65.1%, whereas 3% validamycin suppressed this disease by 88.5%.

Summary: 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. Keywords: Catheter-related bloodstream infection, Kodamaea ohmeri, Caspofungin, Case report

BACKGROUND Opportunistic pathogenic yeast species are frequently associated with water habitats that have pollution sources of human or animal origin. Candida albicans has already been suggested as a faecal indicator microorganism for aquatic environments. OBJECTIVES The goal of this study was to investigate the occurrence of C. albicans and other opportunistic yeasts in sand and seawater samples from beaches in Brazil to assess their correlation with Escherichia coli, and to characterise the pathogenic potential of the yeast isolates. METHODS Opportunistic species (yeasts that grow at 37ºC) were isolated from sand and seawater samples from eight beaches in Brazil during the summer and the winter. Opportunistic yeast species were evaluated for their susceptibility to antifungal drugs, virulence factors, and the in vitro and in vivo biofilm formation. Strains were selected to carry out virulence tests using BALB/c mice. FINDINGS Several water samples could be classified as inappropriate for primary contact recreation in relation to E. coli densities. C. albicans was isolated in low densities. Of the 144 opportunistic yeasts evaluated, 61% displayed resistance or dose-dependent sensitivity to at least one tested drug, and 40% produced proteinase. Strains of C. albicans and Kodamaea ohmeri exhibited the highest rates of adhesion to buccal epithelial cells. All the C. albicans strains that were tested were able to undergo morphogenesis and form a biofilm on catheter fragments in both in vitro and in vivo experiments. It was possible to confirm the pathogenic potential of three of these strains during the disseminated infection test. MAIN CONCLUSIONS The identification of opportunistic yeast species in seawater and sand samples from Brazilian beaches suggest a potential risk to the health of people who use these environments for recreational purposes. ispartof: MEMORIAS DO INSTITUTO OSWALDO CRUZ vol:114 issue:2 pages:1-15 ispartof: location:Brazil status: published

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.

Since, there is no study reporting the mechanism of azole resistance among yeasts isolated from aquatic environments; the present study aims to investigate the occurrence of antifungal resistance among yeasts isolated from an aquatic environment, and assess the efflux-pump activity of the azole-resistant strains to better understand the mechanism of resistance for this group of drugs. For this purpose, monthly water and sediment samples were collected from Catú Lake, Ceará, Brazil, from March 2011 to February 2012. The obtained yeasts were identified based on morphological and biochemical characteristics. Of the 46 isolates, 37 were Candida spp., 4 were Trichosporon asahii, 3 were Cryptococcus laurentii, 1 Rhodotorula mucilaginosa, and 1 was Kodamaea ohmeri. These isolates were subjected to broth microdilution assay with amphotericin B, itraconazole, and fluconazole, according to the methodology standardized by the Clinical and Laboratory Standards Institute (CLSI). The minimum inhibitory concentrations (MICs) of amphotericin B, itraconazole, and fluconazole were 0.03125–2 µg/mL, 0.0625 to ≥16 µg/mL, and 0.5 to ≥64 µg/mL, respectively, and 13 resistant azole-resistant Candida isolates were detected. A reduction in the azole MICs leading to the phenotypical reversal of the azole resistance was observed upon addition of efflux-pump inhibitors. These findings suggest that the azole resistance among environmental Candida spp. is most likely associated with the overexpression of efflux-pumps.

Necrotizing soft tissue infection, NSTI, involves the soft tissue characterized by rapid spread of infection and consequent cell necrosis. NSTI, in particular necrotizing fasciitis (NF), is a significant disease burden in the US with an annual mortality of 4.8 per 1,000,000 person years. Here we describe a rare fungal pathogen, Kodamaea Ohmeri, as a cause of NF in a diabetic but otherwise healthy male patient. In the past K. Ohmeri has been described in children, immunocompromised individuals, and in cases with IV catheters and prolonged use of IV antibiotics. A febrile and hypotensive male (LRINEC score of 6) presented after sustaining abrasions of his right lower extremity. He was initially started on broad-spectrum antibiotics and underwent surgical exploration. During the following weeks, the patient developed sepsis and endured a total of four debridement. Wound cultures resulted K. Ohmeri with sensitivity to miconazole and voriconazole. Anti-fungal, silver dressings and wound vacuum, were utilized to assist in treatment and tissue granulation. To our knowledge, this is the first case describing Kodamea ohmeri as a causative agent of NF. K. Ohmeri should be on the radar of the health care providers taking care of patients with NF, especially in the context of intermittent bouts of sepsis and prolonged hospital course. Our case illustrates the fact that prompt identification, addition of fungal cultures and appropriate surgical treatment are crucial to improve patient outcomes.

Made available in DSpace on 2019-10-04T13:15:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-06-01 The objectives of this study were to identify yeasts in 40 feces samples of Agapornis birds and determine their antifungal susceptibility profile by two methodologies. Results indicated 92.5% of positivity (46 isolates). Six genera were identified (14 species): Cryptococcus (39.13%), four species; Candida (36.96%), four species; Rhodotorula (13.05%), two species; Trichosporon (6.52%), two species; Kodamaea ohmeri (2.17%); and Sporobolomyces salmonicolor (2.17%). Regarding the susceptibility profiles, 41.3% of the isolates showed low sensibility to fluconazole and 47.8% to itraconazole. Thus, Agapornis sp. disseminate potentially pathogenic and resistant yeasts. Precautionary measures should be taken regarding breeding and keeping them as pets. Fac Med Sao Jose do Rio Preto, Lab Microbiol, 5416 Brigadeiro Faria Lima Ave, BR-15090000 Sao Jose Do Rio Preto, Brazil Univ Estadual Paulista, 2265 Cristovao Colombo St, BR-15054000 Sao Jose Do Rio Preto, Brazil Univ Estadual Paulista, 2265 Cristovao Colombo St, BR-15054000 Sao Jose Do Rio Preto, Brazil

Kodamaea ohmeri, also known as Pichia ohmeri, is a yeast belonging to the Saccharomycetes family. In 2012, our hospital has recorded the first case of fungemia caused by K. ohmeri in an 80-year-old male, admitted to intensive care following an acute anterior-lateral myocardial infarction. K. ohmeri grew in blood cultures. Biochemical identification was confirmed using Matrix-Assisted Laser Desorption Ionization-Time of Flight (MALDI-TOF) mass spectrometry and molecular sequencing. Antifungal susceptibility has been performed by broth dilution technique. This case confirms that K. ohmeri is an emergent pathogen even though rarely isolated in human disease. Permanent catheterization is a risk factor and may cause the persistence of a K. ohmeri infection, as well as support treatments (mechanical ventilation, tracheotomy, dialysis). Our therapeutic strategy has been empirical and based exclusively on tested antifungals MIC because EUCAST recommendations does not indicate breakpoints.

Few studies have systematically standardised and evaluated matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) for identification of yeasts from bloodstream infections. This is rapidly becoming pertinent for early identification of yeasts and appropriate antifungal therapy. We used 354 yeast strains identified by polymerase chain reaction (PCR) sequencing for standardisation and 367 blind clinical strains for validation of our MALDI-TOF MS protocols. We also evaluated different sample preparation methods and found the on-plate formic acid extraction method as most cost- and time-efficient. The MALDI-TOF assay correctly identified 98.9% of PCR-sequenced yeasts. Novel main spectrum projections (MSP) were developed for Candida auris, C. viswanathii and Kodamaea ohmeri, which were missing from the Bruker MALDI-TOF MS database. Spectral cut-offs computed by receiver operating characteristics (ROC) analysis showed 99.4% to 100% accuracy at a log score of ≥1.70 for C. tropicalis, C. parapsilosis, C. pelliculosa, C. orthopsilosis, C. albicans, C. rugosa, C. guilliermondii, C. lipolytica, C. metapsilosis, C. nivariensis. The differences in the species-specific scores of our standardisation and blind validation strains were not statistically significant, implying the optimal performance of our test protocol. The MSPs of the three new species also were validated. We conclude that MALDI-TOF MS is a rapid, accurate and reliable tool for identification of bloodstream yeasts. With proper standardisation, validation and regular database expansion, its efficiency can be further enhanced.

Common green lacewing, Chrysoperla zastrowi sillemi is one of the important biological control agents and is used effectively to manage various insect pests. Chrysopid predators are found to harbor many endosymbiotic yeasts and bacteria. Keeping this in view, a study on the distribution of yeast and bacteria in the adult diverticulum and larval gut was conducted using transmission electron microscopy (TEM) and molecular techniques. TEM showed the presence of a load of bacterial cells towards the periphery of inner side of the epithelial lining and the dividing bacterial cells in the larval gut. Numerous oval and kidney shaped yeast fauna were found to be distributed within the lumen and diverticular folds of the diverticulum of adult. Our study reveals the presence and distribution of yeast and bacterial cells from the adult diverticulum and gut of larva. Microbial isolates were identified by sequencing 16S rRNA gene for bacteria and ITS region of yeast including partial rRNA genes ITS-1 and partial 5.8S rRNA gene for yeast, respectively which revealed the presence of yeast isolates namely Kodamaea ohmeri, Torulaspora delbrueckii, Wickerhamomyces anomalus and bacterial isolates namely: Enterobacter hormaechei, E. cloacae and Enterobacter sp. as most common from adult and larvae, respectively. Key words: Diverticulum, diverticular folds, epithelial lining, lumen, yeast, bacteria

Fungal infections have become an important cause of morbidity and mortality in hospitalized children due to many complicating and underlying conditions. We present the case of a newborn infant with fungemia due to Kodamaea ohmeri who had a good outcome of the infection after using the combination of antifungal treatment and central venous catheter removal. COL0058784

Made available in DSpace on 2013-08-12T18:39:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-01-01 Made available in DSpace on 2013-09-30T18:34:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T14:04:28Z No. of bitstreams: 1 S0036-46652012000100004.pdf: 200291 bytes, checksum: 3d68bdf8c27bb5742e75037b796eef8c (MD5) Made available in DSpace on 2014-05-20T14:04:28Z (GMT). No. of bitstreams: 1 S0036-46652012000100004.pdf: 200291 bytes, checksum: 3d68bdf8c27bb5742e75037b796eef8c (MD5) Previous issue date: 2012-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Pró-Reitoria de Pesquisa da UNESP (PROPe UNESP) Introduction: In HIV-infected patients, colonization of the oral cavity by potential pathogenic yeast may lead to development of systemic fungemia. We evaluated the prevalence of yeast in the oral cavity of Brazilian HIV-positive patients and verified whether or not the species characterized were enzymatically active. Furthermore, the species identified were tested for their susceptibility to antifungal treatment. Methods: Patient saliva and oropharyngeal candidiasis samples were collected from 60 seropositive HIV patients and identified by the API20C system. Enzymatic activity was evaluated by the production of proteinase and phospholipase. Susceptibility to antifungal treatments were determined using the broth microdilution method. Results: the most commonly isolated species were C. albicans (51.56%) followed by non-albicans Candida species (43.73%), Trichosporon mucoides (3.12%) and Kodamaea ohmeri (1.56%). Oral colonization by association of different species was observed in 42% of the patients. Enzymatic activity was verified in most of species isolated, except for C. glabrata, C. lusitaniae and C. guilliermondii. Resistance to Fluconazole and Amphotericin B was observed in isolates of C. albicans, C. glabrata, C. parapsilosis, C. krusei, and K. ohmeri. Conclusion: HIV-positive patients are orally colonized by single or multiple species of yeast that are occasionally resistant to Fluconazole or Amphotericin B. Univ Estadual Paulista UNESP, Dept Biosci & Oral Diag, BR-12245000 Sao Jose Dos Campos, SP, Brazil Emilio Ribas Inst Infectol, BR-01246900 São Paulo, Brazil Univ Estadual Paulista UNESP, Dept Biosci & Oral Diag, BR-12245000 Sao Jose Dos Campos, SP, Brazil FAPESP: 2009/52283-0

The biofilms formed by opportunistic yeasts serve as a persistent reservoir of infection and impair the treatment of fungal diseases. The aim of this study was to evaluate photodynamic inactivation (PDI) of biofilms formed by Candida spp. and the emerging pathogens Trichosporon mucoides and Kodamaea ohmeri by a cationic nanoemulsion of zinc 2,9,16,23-tetrakis(phenylthio)-29H,31H-phthalocyanine (ZnPc). Biofilms formed by yeasts after 48 h in the bottom of 96-well microtiter plates were treated with the photosensitizer (ZnPc) and a GaAlAs laser (26.3 J cm(-2)). The biofilm cells were scraped off the well wall, homogenized, and seeded onto Sabouraud dextrose agar plates that were then incubated at 37°C for 48 h. Efficient PDI of biofilms was verified by counting colony-forming units (CFU/ml), and the data were submitted to analysis of variance and the Tukey test (p

Mangrove wetland is a unique ecosystem and has rich bioresources. In this article, the roots, stems, branches, leaves, barks, fruits, and flowers from 12 species of the mangrove plants and six species of the accompanying mangrove plants, seawater and sediments in mangrove ecosystems in China were used as sources for isolation of yeasts. A total of 269 yeasts strains were obtained from the samples. The results of routine identification and phylogenetic analysis showed that they belonged to 22 genera and 45 species. Of all the 269 strains, Candida spp. was predominant with the proportion of 44.61%, followed by Kluyveromyces spp. (8.55%), Pichia spp. (7.44%), Kodamaea ohmeri (5.58%), Issatchenkia spp. (4.83%) and Debaryomyces hansenii (4.46%). We also found that strains N02-2.3 and ST3-1Y3 belonged to the undescribed species of Pichia sp. and Trichosporon sp. respectively while strain HN-12 was not related to any known yeast strains. This means that different yeast strains of Candida spp. especially C. tropicalis were widely distributed in the mangrove ecosystems and may have an important role in the mangrove ecosystems. The results also showed that some of them may have potential applications.

A 43-year-old man with a history of rheumatoid heart disease developed endocarditis. Blood culture showed endocarditis was caused by Kodamaea ohmeri and the susceptibility test showed the yeast species were susceptible to itraconazole, amphotericin B, and voriconazole, but susceptible-dose dependent to fluconazole, and resistant to 5-flucytosine. Treated with surgery and anti-fungi agents, the patient recovered from endocarditis. This is the first case of K. ohmeri fungemia found in Chinese from mainland. More and more evidence indicate that K. ohmeri is an important opportunistic pathogen for human beings.

This study aimed to examine the diversity and ecology of yeasts associated with traditional Egyptian dairy products employing molecular techniques in yeast identification. A total of 120 samples of fresh and stored Domiati cheese, kariesh cheese, and "Matared" cream were collected from local markets and examined. Forty yeast isolates were cultured from these samples and identified using the restriction-fragment length polymorphism (RFLPs) of 5.8S-ITS rDNA region and sequencing of the domains D1 and D2 of the 26S rRNA gene. Yeasts were identified as Issatchenkia orientalis (13 isolates), Candida albicans (4 isolates), Clavispora lusitaniae (Candida lusitaniae) (9 isolates), Kodamaea ohmeri (Pichia ohmeri) (1 isolate), Kluyveromyces marxianus (6 isolates), and Candida catenulata (7 isolates). With the exception of C. lusitaniae, the D1/D2 26S rRNA gene sequences were 100% identical for the yeast isolates within the same species. Phylogenetic reconstruction of C. lusitaniae isolates grouped them into 3 distinguished clusters. Kariesh cheese was found to be the most diverse in its yeast floras and contained the highest total yeast count compared with other examined dairy products. This was linked to the acidic pH and lower salt content of this cheese, which favor the growth and survival of yeasts in foodstuffs. Stored Domiati cheese also contained diverse yeast species involving isolates of the pathogenic yeast C. albicans. This raises the possibility of dairy products being vehicles of transmission of pathogenic yeasts.

Three ascomycetous yeast strains were isolated from decaying green wine grapes, collected from Hyderabad city in India. Two strains, YS9 and YS21, were identified as Kodamaea ohmeri and Candida fermentati, respectively. The third strain, YS12(T), differs from Candida parapsilosis, Candida orthopsilosis and Candida metapsilosis, the nearest phylogenetic neighbours, by 1.6-1.9% with respect to the nucleotide sequence of the D1/D2 domain of the 26S rRNA gene and by 1.4-9.2% with respect to the nucleotide sequence of the internal transcribed spacer 1 (ITS1)-5.8S rRNA gene-ITS2 region. YS12(T) also differs from C. parapsilosis, C. metapsilosis and C. orthopsilosis by some phenotypic characteristics. Thus, based on the phenotypic differences and phylogenetic analysis, strain YS12(T) is assigned the status of a new species of Candida, for which the name C. hyderabadensis sp. nov. is proposed. The type strain is YS12(T) (NRRL Y-27953(T)=CBS10444(T)=IAM15334(T)).

Data on clinical isolates of Kodamaea ( Pichia ) ohmeri , an emerging fungal pathogen, are scarce. Over the past 5 years, we identified yeast isolates from nine patients with fungemia as K. ohmeri by using the API 20C system. Here, we reanalyzed these isolates first by sequencing the internal transcribed spacer 2 (ITS2) regions and then by growing the isolates on CHROMagar Candida medium and subjecting them to pulsed-field gel electrophoresis (PFGE). Based on their ITS2 sequences, six of the nine isolates were confirmed as K. ohmeri , while the others were identified as Candida haemulonii ( n = 2) and Candida parapsilosis ( n = 1). PFGE karyotyping of the K. ohmeri isolates revealed similar major bands, and their colonies showed a characteristic color change from pink to blue when grown on CHROMagar Candida medium for more than 48 h. For K. ohmeri , the ranges of MICs of fluconazole, voriconazole, caspofungin, and micafungin were 2 to 32 μg/ml, 0.03 to 0.5 μg/ml, 0.125 to 0.25 μg/ml, and 0.03 to 0.06 μg/ml, respectively. Restriction endonuclease analysis of genomic NotI-digested DNA (REAG-N) from isolates from different patients produced unique patterns, suggesting that the fungemia had occurred sporadically. This study determined that ITS2 sequence data, PFGE karyotypes, and CHROMagar Candida chromogenic culture medium are reliable diagnostic tools for identifying K. ohmeri while REAG-N is useful for genotyping the clinical isolates of K. ohmeri .

Systemic fungal infection related to fluconazole-resistant yeasts are emerging in immunocompromised patients. In this case-series, we report eight cases of fungemia caused by Trichosporon spp. (2), Stephanoascus ceferrii (1), Kodamaea ohmeri (1), Pichia kutrawersi (2), Candida rugosa (1) and Candida lusitianae (1) in immunocompromised patients. All the yeasts except (Trichosporon asahii) were sequenced. As these rare species are inherently resistant to antifungal agents and they may lead to the development of nosocomial outbreaks, therefore, accurate identification followed by antifungal susceptibility testing is crucial for proper treatment and management.

Soy-daddawa, a fermented soybean (Glycine max (L.) Merr.) condiment, plays a significant role in the culinary practice of West Africa. It is essential to understand the microbial community of soy-daddawa for a successful starter culture application. This study investigated the microbial community structure of soy-daddawa samples collected from Nigerian markets, by PCR-denaturing gradient gel electrophoresis (DGGE) targeting the V3-V5 region of the 16S rRNA gene of bacteria and internal transcribed spacer 2 (ITS2) region of fungi. Six bacterial and 16 fungal (nine yeasts and seven molds) operational taxonomic units (OTUs)/species were obtained at 97% sequence similarity. Taxonomic assignments revealed that bacterial OTUs belonged to the phyla Firmicutes and Actinobacteria, and included species from the genera Atopostipes, Bacillus, Brevibacterium and Nosocomiicoccus. Densitometric analysis of DGGE image/bands revealed that Bacillus spp. were the dominant OTU/species in terms of population numbers. Fungal OTUs belonged to the phyla Ascomycota and Zygomycota, and included species from the genera, Alternaria, Aspergillus, Candida, Cladosporium, Dokmaia, Issatchenkia, Kodamaea, Lecythophora, Phoma, Pichia, Rhizopus, Saccharomyces and Starmerella. The majority of fungal species have not been previously reported in soy-daddawa. Potential opportunistic human pathogens such as Atopostipes suicloacalis, Candida rugosa, Candida tropicalis, and Kodamaea ohmeri were detected. Variation in soy-daddawa microbial communities amongst samples and presence of potential opportunistic pathogens emphasises the need for starter culture employment and good handling practices in soy-daddawa processing.

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. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Summary Kodamaea ohmeri is an unusual yeast-form fungus that has recently been identified as an important aetiological agent of fungaemia, endocarditis, cellulitis, funguria and peritonitis in immunocompromised patients. We present two new isolated of K. ohmeri. The microorganisms were identified by CHROMagar Candida medium, VitekII system and API ID32C. Biochemical identification of the two yeast isolates was confirmed by sequence analysis of the 26S ribosomal DNA. Antifungal susceptibility testing done by Sensititre YeastOne showed that the isolates were susceptible to amphotericin B, voriconazole and itraconazole. This work is the first report of isolation of K. ohmeri in immunocompromised patients in Italy.

Sir,Kodamaea ohmeri (previously known as Pichia ohmeri) is commonly used in the food industry because of its biochemical properties of fermentation (as in pickles and fruits).1 More reports are eme...

Kodamaea ohmeri is a yeast that rarely causes human infections. The first case of K. ohmeri fungaemia in a premature neonate is reported; it was successfully treated with liposomal amphotericin B. Biochemical identification of the yeast was performed by Vitek II and API and was confirmed by rRNA gene sequencing. K. ohmeri as a human pathogenic yeast is uncommon to hospitalized neonates and immunocompromised individuals.

The frequency of opportunistic fungal infections has increased over the last decade, possibly as a result of the increasing number of susceptible hosts, due to the use of aggressive chemotherapy, i...

UNLABELLED Ruminal organic acid production, especially lactic acid, can be modified by feeding cattle highly concentrated diets, which have been shown to adversely affect dairy cattle health. Therefore, the use of lactic acid-utilizing organisms is considered to be a potential method for controlling lactic acid levels. This study was conducted to isolate and identify lactic acid-utilizing yeasts from the ruminal fluid of dairy cattle and to determine the specific growth rate and generation time when using lactic acid as a carbon source instead of glucose. Seventeen yeast isolates were examined in this study. Yeasts isolated from dairy cattle that were fed a high cassava pulp diet (HCP) had higher specific growth rates and shorter generation times than yeasts isolated from dairy cattle that were fed a high-concentrate diet (HC) and a mixed diet (M). The three most effective yeasts in terms of specific growth rate and generation time were Pichia kudriavzevii, Candida rugosa and Kodamaea ohmeri, with 99, 100 and 99% nucleotide identities, respectively. These three isolates could be used as potential probiotics in dairy cattle diets. SIGNIFICANCE AND IMPACT OF THE STUDY This study demonstrates that yeasts isolated from the ruminal fluid of dairy cattle can utilize lactic acid as a carbon and energy source for growth. The isolated yeasts can be used as probiotic supplements for dairy cattle that are fed highly concentrated diets to reduce ruminal lactic acid production.

The objective of this study was to isolate and identify yeast strains from broilers excreta and to evaluate in vitro their potential for probiotic use in animal production. Methods and results Nine yeast strains were isolated and presumptively pre-identified by biochemical assays. These isolates were grouped in six different molecular profiles using PCR-fingerprinting technique. Each profile was identified by sequencing of the D1/D2 domains of the large subunit of the 26S rRNA gene. These yeasts were identified as: Trichosporon sp. (LV-2), Wickerhamomyces anomalus (LV-6), Pichia kudriavzevii (LV-8), Kodamaea ohmeri (LV-9) and Trichosporon asahii (LV-10). A pre-screening of the strains for probiotic use was based on their ability to agglutinate pathogenic micro-organisms. These yeast strains were characterized for specific growth rate, duplication time, their cell surface hydrophobicity, medium acidification, resistance to low pH (2.0, 2.5 and 3.0) and concentrations of bile salts (0.3% and 0.6%). The isolate of W. anomalus (LV-6) had the highest agglutinating and adherence capacity, a growth rate of 2.07 × 10 8 cfu/mL in 24 h at 30 °C, decreasing the medium pH from 6.5 to 5.23, a 25% hydrophobicity and an elevated capacity to grow under stress conditions. Conclusions W. anomalus strain LV-6 showed the best characteristics for use as a probiotic candidate. Significance and impact of the Study: The data from this study helped in choosing a probiotic candidate from yeast to use in broiler production.

This study investigated the diversity and dynamics of yeasts involved in alcoholic fermentation of a traditional sorghum beer from Côte d'Ivoire, tchapalo. A total of 240 yeast strains were isolated from fermenting sorghum wort inoculated with dry yeast from two geographic regions of Côte d'Ivoire (Abidjan and Bondoukou). Initial molecular identification to the species level was carried out using RFLP of PCR-amplified internal transcribed spacers of rDNA (ITS1-5.8S-ITS2). Ten different profiles were obtained from the restriction of PCR products with the three endonucleases HaeIII, CfoI and HinfI. Sequence analysis of the D1/D2 domain of the 26S rDNA and the ACT1 gene allowed us to assign these groups to six different species: Saccharomyces cerevisiae-like, Candida tropicalis, Pichia kudriavzevii, Pichia kluyveri, Kodamaea ohmeri and Meyerozyma caribbica. The most frequent species associated with tchapalo fermentation was S. cerevisiae-like (87.36%), followed by C. tropicalis (5.45%) and M. caribbica (2.71%). S. cerevisiae-like strains were diploid heterozygotes and exhibited three to four nucleotides divergence from the type strain in the D1/D2 domain and several indels in the more discriminant sequence of the intron of the ACT1 gene. During the process, the yeast species isolated and their frequencies varied according to the geographic origin of the dry yeast. The occurrence of some species was sporadic and only two non-Saccharomyces species were found in the final product.

Kodamaea (Pichia) ohmeri is an unusual yeast-form fungus that has recently been identified as an important etiology of fungemia, endocarditis, cellulitis, funguria and peritonitis in immunocompromised patients. We report a case of K. ohmeri fungemia in a 34-year-old hospitalized patient with thrombophlebitis. The patient was admitted to the hospital for evaluation and management of an acquired tracheo-esophageal fistula secondary to an impacted denture. Fever developed on hospital day 22, and physical exam revealed right arm superficial thrombophlebitis at the site of the peripheral venous catheter that was confirmed by Doppler ultrasound. The peripheral vein was removed and blood cultures from hospital day 22 and 23 grew yeast species. The yeast was subsequently identified to be K. ohmeri by Vitek II and API20C and was confirmed by 18S rRNA gene sequencing. The fungemia and right arm phlebitis was successfully treated with a 2-week course of micafungin therapy. This is the first case of K. ohmeri fungemia in a patient that was successfully treated with micafungin.

A rapid molecular identification technique was applied on microbial microflora isolated from Brazilian cassava roots given a yeast profile presented in the samples analyzed. A total of 24 strain isolated from cassava were initially grouped and identified in five groups using restriction-fragment length polymorphism (RFLPs) of 5.8S-ITS rDNA region. Sequencing analysis of the domains D1 and D2 of the 26S rRNA gene or 5.8S rRNA-ITS region were used to identify different groups of yeasts. Representative colonies of yeasts of each group were isolated and identified as Debaromyces hansenii, Kodamaea ohmeri, Candida glabrata, C. haemulonii, and Pichia gullhermondii. It is hoped that these results will contribute toward selecting yeast from this microflora capable to degrade cassava starch in the near future.

Background/Purpose The yeast Kodamaea ohmeri rarely causes life-threatening human infections. However, risk factors, laboratory diagnoses, and treatments for K. ohmeri infection have been limited, and the optimal therapy for K. ohmeri infection has not been identified. Methods Twenty cases of K. ohmeri infection have been reported in the English medical literature. We present two new cases of K. ohmeri fungemia. We investigated the nature and treatment of K. ohmeri infections using minimum inhibitory concentrations of antifungal agents and by comparing the two cases with those described in the literature. Results From March 1998 to December 2008, a total of 22 patients with K. ohmeri infections were studied. Hematological malignancies and diabetes were the most common co-morbidities for K. ohmeri infections, with crude prevalence rates of 27.3% and 18.2%, respectively. The K. ohmeri isolates showed less susceptibility to fluconazole but greater susceptibility to amphotericin B [15/25 isolates (60%) vs. 25/25 isolates (100%), respectively]. Good outcomes (8/9 cases; 88.9%) were found following removal of indwelling catheters and implants. In addition, voriconazole and echinocandins, such as caspofungin and micafungin, also showed excellent minimum inhibitory concentrations against K. ohmeri . Conclusion K. ohmeri should not be regarded as a contaminant of blood cultures. Favorable outcomes for this potentially life-threatening infection are promoted by the removal of indwelling catheters; furthermore, outcomes are associated with optimal antifungal regimens, especially voriconazole and echinocandins.

Kodamaea ohmeri was isolated from a 38-year-old HIV seropositive woman with pseudomembranous oral candidiasis. The isolate was identified by the API 20 C yeast identification system and confirmed by sequence analysis. Antifungal susceptibility testing done by E-test showed that the isolate was susceptible to voriconazole, amphotericin B and caspofungin.