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Omura M, Satoh K, Tamura T, Komori A, Makimura K. Molecular epidemiological investigation of Cryptococcus spp. carried by captive koalas ( Phascolarctos cinereus) in Japan. Microbiol Spectr 2024; 12:e0290323. [PMID: 38411053 DOI: 10.1128/spectrum.02903-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 01/26/2024] [Indexed: 02/28/2024] Open
Abstract
Cryptococcus neoformans and Cryptococcus gattii cause cryptococcosis, a systemic mycosis that infects a wide range of species. Recent molecular biological investigations have allowed for the genotyping of these species, providing more detailed information on their pathogenicity and infection routes. Koalas (Phascolarctos cinereus) are frequently colonized by Cryptococcus spp., but molecular epidemiological studies have yet to be conducted in Japan. Here, we conducted multi-locus sequence typing (MLST) analysis on Cryptococcus spp. colonization isolates obtained from all koalas kept in seven parks across Japan. Out of 46 koalas examined, 10 (22%) were positive for C. gattii and 3 (6.5%) were positive for C. neoformans. All C. gattii isolates belonged to molecular type VGI and were either sequence type (ST) 51 or a novel ST, and all C. neoformans isolates belonged to molecular type VNI and ST23. Despite the frequent movement of koalas between parks, the STs were relatively park-specific, suggesting that the floor of the rearing barns is a source of infection and may act as a reservoir. MLST analysis confirmed that C. gattii was transported, established, and spread by koalas in areas where C. gattii was not originally present. MLST analysis is considered useful in assessing the pathogenicity and tracing the transmission routes of Cryptococcus spp. carried by koalas.IMPORTANCEThis is the first study to conduct a multi-locus sequence typing analysis on Cryptococcus spp. carried by captive koalas in Japan. Cryptococcosis remains a globally high-fatality fungal infection in humans, and captive koalas are known to carry a high percentage of Cryptococcus spp. Through this research, the molecular types and transmission routes of Cryptococcus spp. carried by koalas have been elucidated, revealing the potential role of enclosure flooring as a reservoir. It has been confirmed that Cryptococcus gattii, which is not endemic in Japan, has become established through koalas and is spreading to new individuals in Japan. This study is believed to provide valuable insights into koala conservation and contribute to the One Health approach for Cryptococcosis, a zoonotic infection.
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Affiliation(s)
- Miki Omura
- Laboratory of Medical Mycology, Graduate School of Medicine, Teikyo University, Tokyo, Japan
| | - Kazuo Satoh
- Teikyo University Institute of Medical Mycology, Tokyo, Japan
| | - Takashi Tamura
- Teikyo University Institute of Medical Mycology, Tokyo, Japan
| | - Aya Komori
- Teikyo University Institute of Medical Mycology, Tokyo, Japan
| | - Koichi Makimura
- Laboratory of Medical Mycology, Graduate School of Medicine, Teikyo University, Tokyo, Japan
- Teikyo University Institute of Medical Mycology, Tokyo, Japan
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Hong N, Chen M, Xu J. Molecular Markers Reveal Epidemiological Patterns and Evolutionary Histories of the Human Pathogenic Cryptococcus. Front Cell Infect Microbiol 2021; 11:683670. [PMID: 34026667 PMCID: PMC8134695 DOI: 10.3389/fcimb.2021.683670] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Accepted: 04/22/2021] [Indexed: 01/02/2023] Open
Abstract
The human pathogenic Cryptococcus species are the main agents of fungal meningitis in humans and the causes of other diseases collectively called cryptococcosis. There are at least eight evolutionary divergent lineages among these agents, with different lineages showing different geographic and/or ecological distributions. In this review, we describe the main strain typing methods that have been used to analyze the human pathogenic Cryptococcus and discuss how molecular markers derived from the various strain typing methods have impacted our understanding of not only cryptococcal epidemiology but also its evolutionary histories. These methods include serotyping, multilocus enzyme electrophoresis, electrophoretic karyotyping, random amplified polymorphic DNA, restriction fragment length polymorphism, PCR-fingerprinting, amplified fragment length polymorphism, multilocus microsatellite typing, single locus and multilocus sequence typing, matrix-assisted laser desorption/ionization time of flight mass spectrometry, and whole genome sequencing. The major findings and the advantages and disadvantages of each method are discussed. Together, while controversies remain, these strain typing methods have helped reveal (i) the broad phylogenetic pattern among these agents, (ii) the centers of origins for several lineages and their dispersal patterns, (iii) the distributions of genetic variation among geographic regions and ecological niches, (iv) recent hybridization among several lineages, and (v) specific mutations during infections within individual patients. However, significant challenges remain. Multilocus sequence typing and whole genome sequencing are emerging as the gold standards for continued strain typing and epidemiological investigations of cryptococcosis.
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Affiliation(s)
- Nan Hong
- Department of Dermatology, Shanghai Key Laboratory of Medical Mycology, Changzheng Hospital, Naval Medical University, Shanghai, China.,Department of Burn and Plastic Surgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Min Chen
- Department of Dermatology, Shanghai Key Laboratory of Medical Mycology, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Jianping Xu
- Department of Biology, McMaster University, Hamilton, ON, Canada
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Probert M, Zhou X, Goodall M, Johnston SA, Bielska E, Ballou ER, May RC. A Glucuronoxylomannan Epitope Exhibits Serotype-Specific Accessibility and Redistributes towards the Capsule Surface during Titanization of the Fungal Pathogen Cryptococcus neoformans. Infect Immun 2019; 87:IAI.00731-18. [PMID: 30670549 PMCID: PMC6434129 DOI: 10.1128/iai.00731-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Accepted: 12/23/2018] [Indexed: 11/20/2022] Open
Abstract
Disseminated infections with the fungal species Cryptococcus neoformans or, less frequently, Cryptococcus gattii are an important cause of mortality in immunocompromised individuals. Central to the virulence of both species is an elaborate polysaccharide capsule that consists predominantly of glucuronoxylomannan (GXM). Due to its abundance, GXM is an ideal target for host antibodies, and several monoclonal antibodies (mAbs) have previously been derived using purified GXM or whole capsular preparations as antigens. In addition to their application in the diagnosis of cryptococcosis, anti-GXM mAbs are invaluable tools for studying capsule structure. In this study, we report the production and characterization of a novel anti-GXM mAb, Crp127, that unexpectedly reveals a role for GXM remodeling during the process of fungal titanization. We show that Crp127 recognizes a GXM epitope in an O-acetylation-dependent, but xylosylation-independent, manner. The epitope is differentially expressed by the four main serotypes of Cryptococcus neoformans and C. gattii, is heterogeneously expressed within clonal populations of C. gattii serotype B strains, and is typically confined to the central region of the enlarged capsule. Uniquely, however, this epitope redistributes to the capsular surface in titan cells, a recently characterized morphotype where haploid 5-μm cells convert to highly polyploid cells of >10 μm with distinct but poorly understood capsular characteristics. Titan cells are produced in the host lung and critical for successful infection. Crp127 therefore advances our understanding of cryptococcal morphological change and may hold significant potential as a tool to differentially identify cryptococcal strains and subtypes.
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Affiliation(s)
- Mark Probert
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Xin Zhou
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Margaret Goodall
- Institute of Immunology and Immunotherapy, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Simon A Johnston
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
- Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Ewa Bielska
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Elizabeth R Ballou
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Robin C May
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
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Genotypic Diversity Is Independent of Pathogenicity in Colombian Strains of Cryptococcus neoformans and Cryptococcus gattii in Galleria mellonella. J Fungi (Basel) 2018; 4:jof4030082. [PMID: 29976849 PMCID: PMC6162678 DOI: 10.3390/jof4030082] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 06/29/2018] [Accepted: 06/30/2018] [Indexed: 12/15/2022] Open
Abstract
Cryptococcosis is a potentially fatal opportunistic mycosis that affects the lungs and central nervous system. It has been suggested that certain strains of C. neoformans/C. gattii may have the potential to be more virulent according to the molecular type. This study aims to investigate the association between virulence in the G. mellonella model and genotypic diversity of Colombian clinical and environmental isolates of C. neoformans/C. gattii. A total of 33 clinical and 12 environmental isolates were selected according to their geographical origin and sequence types (STs). Pathogenicity was determined using the G. mellonella model, and the cell and capsular size before and after inoculation was determined. For C. neoformans, virulence in G. mellonella revealed that death occurred on average on day 6 (p < 0.05) and that ST5C, 6C, 25C and 71C were the most virulent. In C. gattii, death occurred at 7.3 days (p < 0.05), and ST47C, 58C, 75A and 106C were the most virulent. Capsular size increased for both species after passage in G. mellonella. In conclusion, the pathogenicity of Cryptococcus strains in the G. mellonella invertebrate model is independent of molecular type or pathogenicity factor, even within the same ST, but it is possible to find variable degrees of pathogenicity.
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Vreulink JM, Khayhan K, Hagen F, Botes A, Moller L, Boekhout T, Vismer H, Botha A. Presence of pathogenic cryptococci on trees situated in two recreational areas in South Africa. FUNGAL ECOL 2017. [DOI: 10.1016/j.funeco.2017.09.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Roberto TN, Rodrigues AM, Hahn RC, de Camargo ZP. Identifying Paracoccidioides phylogenetic species by PCR-RFLP of the alpha-tubulin gene. Med Mycol 2015; 54:240-7. [PMID: 26667263 DOI: 10.1093/mmy/myv083] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 08/16/2015] [Indexed: 11/12/2022] Open
Abstract
Paracoccidioidomycosis is an important systemic fungal infection that occurs throughout Latin America. The etiological agents comprise a species complex that includes two major groups: P. brasiliensis (including subgroups S1, PS2, and PS3) and P. lutzii. A great number of phenotypes may overlap, especially among closely related groups, discouraging the use of morphology alone for species recognition. To overcome this problem, here we propose identifying cryptic Paracoccidioides spp. using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) of the alpha-tubulin (TUB1) gene. In silico analysis of 90 TUB1 sequences led to the identification of two restriction enzymes with the potential to identify Paracoccidioides: Bcl I and Msp I. A portion of the TUB1 gene was amplified and double digested in vitro with the Bcl I and Msp I endonucleases, which generated four different electrophoretic patterns corresponding to the four main genetic groups: S1, PS2, and PS3 of P. brasiliensis and P. lutzii. The major P. brasiliensis group recognized was S1 (n = 17; 42.5%), followed by PS2 (n = 9; 22.5%) and PS3 (n = 6; 15%). A total of eight (20%) P. lutzii isolates were identified, mainly from midwestern Brazil. Our data revealed that TUB1-RFLP is an efficient, fast, and inexpensive tool for identifying Paracoccidioides spp., which may be directly applied to the molecular epidemiological studies of paracoccidioidomycosis.
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Affiliation(s)
- Thiago Nunes Roberto
- Department of Microbiology, Immunology and Parasitology, Cellular Biology Division, Federal University of São Paulo, São Paulo, Brazil
| | - Anderson Messias Rodrigues
- Department of Microbiology, Immunology and Parasitology, Cellular Biology Division, Federal University of São Paulo, São Paulo, Brazil
| | - Rosane Christine Hahn
- Núcleo de Doenças Infecciosas e Tropicais, Universidade Federal do Mato Grosso (UFMT), Cuiabá, MT, Brazil
| | - Zoilo Pires de Camargo
- Department of Microbiology, Immunology and Parasitology, Cellular Biology Division, Federal University of São Paulo, São Paulo, Brazil
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Abstract
Understanding of the taxonomy and phylogeny of Cryptococcus gattii has been advanced by modern molecular techniques. C. gattii probably diverged from Cryptococcus neoformans between 16 million and 160 million years ago, depending on the dating methods applied, and maintains diversity by recombining in nature. South America is the likely source of the virulent C. gattii VGII molecular types that have emerged in North America. C. gattii shares major virulence determinants with C. neoformans, although genomic and transcriptomic studies revealed that despite similar genomes, the VGIIa and VGIIb subtypes employ very different transcriptional circuits and manifest differences in virulence phenotypes. Preliminary evidence suggests that C. gattii VGII causes severe lung disease and death without dissemination, whereas C. neoformans disseminates readily to the central nervous system (CNS) and causes death from meningoencephalitis. Overall, currently available data indicate that the C. gattii VGI, VGII, and VGIII molecular types more commonly affect nonimmunocompromised hosts, in contrast to VGIV. New, rapid, cheap diagnostic tests and imaging modalities are assisting early diagnosis and enabling better outcomes of cerebral cryptococcosis. Complications of CNS infection include increased intracranial pressure, severe neurological sequelae, and development of immune reconstitution syndrome, although the mortality rate is low. C. gattii VGII isolates may exhibit higher fluconazole MICs than other genotypes. Optimal therapeutic regimens are yet to be determined; in most cases, initial therapy with amphotericin B and 5-flucytosine is recommended.
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Hagen F, Khayhan K, Theelen B, Kolecka A, Polacheck I, Sionov E, Falk R, Parnmen S, Lumbsch HT, Boekhout T. Recognition of seven species in the Cryptococcus gattii/Cryptococcus neoformans species complex. Fungal Genet Biol 2015; 78:16-48. [PMID: 25721988 DOI: 10.1016/j.fgb.2015.02.009] [Citation(s) in RCA: 452] [Impact Index Per Article: 50.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 02/12/2015] [Accepted: 02/15/2015] [Indexed: 02/08/2023]
Abstract
Phylogenetic analysis of 11 genetic loci and results from many genotyping studies revealed significant genetic diversity with the pathogenic Cryptococcus gattii/Cryptococcus neoformans species complex. Genealogical concordance, coalescence-based, and species tree approaches supported the presence of distinct and concordant lineages within the complex. Consequently, we propose to recognize the current C. neoformans var. grubii and C. neoformans var. neoformans as separate species, and five species within C. gattii. The type strain of C. neoformans CBS132 represents a serotype AD hybrid and is replaced. The newly delimited species differ in aspects of pathogenicity, prevalence for patient groups, as well as biochemical and physiological aspects, such as susceptibility to antifungals. MALDI-TOF mass spectrometry readily distinguishes the newly recognized species.
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Affiliation(s)
- Ferry Hagen
- CBS-KNAW Fungal Biodiversity Centre, Basidiomycete and Yeast Research, Utrecht, The Netherlands; Department of Medical Microbiology and Infectious Diseases, Canisius-Wilhelmina Hospital, Nijmegen, The Netherlands
| | - Kantarawee Khayhan
- CBS-KNAW Fungal Biodiversity Centre, Basidiomycete and Yeast Research, Utrecht, The Netherlands; Department of Microbiology and Parasitology, Faculty of Medical Sciences, University of Phayao, Phayao, Thailand
| | - Bart Theelen
- CBS-KNAW Fungal Biodiversity Centre, Basidiomycete and Yeast Research, Utrecht, The Netherlands
| | - Anna Kolecka
- CBS-KNAW Fungal Biodiversity Centre, Basidiomycete and Yeast Research, Utrecht, The Netherlands
| | - Itzhack Polacheck
- Department of Clinical Microbiology and Infectious Diseases, Hadassah-Hebrew University Medical Center, Ein Kerem, Jerusalem, Israel
| | - Edward Sionov
- Department of Clinical Microbiology and Infectious Diseases, Hadassah-Hebrew University Medical Center, Ein Kerem, Jerusalem, Israel; Department of Food Quality & Safety, Institute for Postharvest and Food Sciences, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
| | - Rama Falk
- Department of Clinical Microbiology and Infectious Diseases, Hadassah-Hebrew University Medical Center, Ein Kerem, Jerusalem, Israel; Department of Fisheries and Aquaculture, Ministry of Agriculture and Rural Development, Nir-David, Israel
| | - Sittiporn Parnmen
- Department of Medical Sciences, Ministry of Public Health, Nonthaburi, Thailand
| | | | - Teun Boekhout
- CBS-KNAW Fungal Biodiversity Centre, Basidiomycete and Yeast Research, Utrecht, The Netherlands; Shanghai Key Laboratory of Molecular Medical Mycology, Changzheng Hospital, Second Military Medical University, Shanghai, China; Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
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Clinical and microbiological characteristics of cryptococcosis in Singapore: predominance of Cryptococcus neoformans compared with Cryptococcus gattii. Int J Infect Dis 2014; 26:110-5. [PMID: 25018090 DOI: 10.1016/j.ijid.2014.05.019] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 05/19/2014] [Accepted: 05/20/2014] [Indexed: 01/17/2023] Open
Abstract
OBJECTIVES To describe the clinical features, treatments, outcomes, and subtype prevalence of cryptococcosis in Singapore. METHODS All patients with laboratory confirmed cryptococcal infections admitted from 1999 to 2007 to a teaching hospital in Singapore were reviewed retrospectively. Identification and molecular types of Cryptococcus neoformans variants and Cryptococcus gattii were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Serotypes were inferred with a multiplex PCR method. RESULTS Of 62 patients with cryptococcosis, C. neoformans var. grubii was the predominant subtype (in 95%), affecting mainly immunocompromised hosts (91%) with HIV infection (80%). Patients with HIV were younger (median age 36.5 vs. 49.5 years, p=0.006) and less likely to present with an altered mental status (14% vs. 50%, p=0.013). In contrast, delayed treatment (median 7 days vs. 2 days, p=0.03), pulmonary involvement (58% vs. 14%, p=0.03), and initial treatment with fluconazole (25% vs. 2%, p=0.02) were more common in HIV-negative patients. C. gattii was uncommon, affecting only three patients, all of whom were immunocompetent and had disseminated disease with pulmonary and neurological involvement. All C. gattii were RFLP type VG II, serotype B and all C. neoformans var. grubii were RFLP type VN I, serotype A, except for one that was RFLP type VN II. CONCLUSION C. neoformans var. grubii, subtype VN I, was the predominant subtype in Singapore, infecting younger, mainly immunocompromised hosts with HIV. C. gattii was uncommon, causing pulmonary manifestations in older, immunocompetent patients and were RFLP type VG II.
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Park SH, Kim M, Joo SI, Hwang SM. Molecular Epidemiology of Clinical Cryptococcus neoformans Isolates in Seoul, Korea. MYCOBIOLOGY 2014; 42:73-78. [PMID: 24808738 PMCID: PMC4004952 DOI: 10.5941/myco.2014.42.1.73] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 02/16/2014] [Accepted: 02/23/2014] [Indexed: 06/03/2023]
Abstract
Cryptococcal infection is primarily caused by two species, Cryptococcus neoformans and C. gattii. Between the two species, C. neoformans var. grubii is the major causative agent of cryptococcosis in Asia. We investigated the molecular characteristics of 46 isolates of C. neoformans from patients with cryptococcosis between 2008 and 2012 in Seoul, Korea. All the isolates were determined to be C. neoformans var. grubii (serotype A), mating type MATα, and molecular type VNI by PCR-restriction fragment length polymorphism of the URA5 gene. Multilocus sequencing type (MLST) analysis using the International Society of Human and Animal Mycoses (ISHAM) consensus MLST scheme identified two sequence types (ST). Out of the 46 strains, 44 (95.7%) were identified as ST5, and remaining 2 were identified as ST31. Our study revealed that the clinical strains of C. neoformans in Korea are genetically homogeneous with the VNI/ST5 genotypes, and new appearance of VNI/ST31 genotype may serve as an important indicator of global genetic analysis.
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Affiliation(s)
- So Hae Park
- Department of Clinical Laboratory Science, Catholic University of Pusan, Busan 609-757, Korea
| | - Mina Kim
- Department of Laboratory Medicine, Ulsan University School of Medicine, Seoul 138-736, Korea
| | - Sei Ick Joo
- Department of Laboratory Medicine, Seoul National University Hospital, Seoul 110-744, Korea
| | - Soo Myung Hwang
- Department of Clinical Laboratory Science, Catholic University of Pusan, Busan 609-757, Korea
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Kaocharoen S, Ngamskulrungroj P, Firacative C, Trilles L, Piyabongkarn D, Banlunara W, Poonwan N, Chaiprasert A, Meyer W, Chindamporn A. Molecular epidemiology reveals genetic diversity amongst isolates of the Cryptococcus neoformans/C. gattii species complex in Thailand. PLoS Negl Trop Dis 2013; 7:e2297. [PMID: 23861989 PMCID: PMC3701708 DOI: 10.1371/journal.pntd.0002297] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 05/23/2013] [Indexed: 12/22/2022] Open
Abstract
To gain a more detailed picture of cryptococcosis in Thailand, a retrospective study of 498 C. neoformans and C. gattii isolates has been conducted. Among these, 386, 83 and 29 strains were from clinical, environmental and veterinary sources, respectively. A total of 485 C. neoformans and 13 C. gattii strains were studied. The majority of the strains (68.9%) were isolated from males (mean age of 37.97 years), 88.5% of C. neoformans and only 37.5% of C. gattii strains were from HIV patients. URA5-RFLP and/or M13 PCR-fingerprinting analysis revealed that the majority of the isolates were C. neoformans molecular type VNI regardless of their sources (94.8%; 94.6% of the clinical, 98.8% of the environmental and 86.2% of the veterinary isolates). In addition, the molecular types VNII (2.4%; 66.7% of the clinical and 33.3% of the veterinary isolates), VNIV (0.2%; 100% environmental isolate), VGI (0.2%; 100% clinical isolate) and VGII (2.4%; 100% clinical isolates) were found less frequently. Multilocus Sequence Type (MLST) analysis using the ISHAM consensus MLST scheme for the C. neoformans/C. gattii species complex identified a total of 20 sequence types (ST) in Thailand combining current and previous data. The Thai isolates are an integrated part of the global cryptococcal population genetic structure, with ST30 for C. gattii and ST82, ST83, ST137, ST141, ST172 and ST173 for C. neoformans being unique to Thailand. Most of the C. gattii isolates were ST7 = VGIIb, which is identical to the less virulent minor Vancouver island outbreak genotype, indicating Thailand as a stepping stone in the global spread of this outbreak strain. The current study revealed a greater genetic diversity and a wider range of major molecular types being present amongst Thai cryptococcal isolates than previously reported.
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Affiliation(s)
- Sirada Kaocharoen
- Mycology Laboratory, King Chulalongkorn Memorial Hospital, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Molecular Mycology Research Laboratory, CIDM, Sydney Medical School - Westmead Hospital, The University of Sydney, Westmead Millennium Institute, Westmead, New South Wales, Australia
| | - Popchai Ngamskulrungroj
- Molecular Mycology Research Laboratory, CIDM, Sydney Medical School - Westmead Hospital, The University of Sydney, Westmead Millennium Institute, Westmead, New South Wales, Australia
- Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Carolina Firacative
- Molecular Mycology Research Laboratory, CIDM, Sydney Medical School - Westmead Hospital, The University of Sydney, Westmead Millennium Institute, Westmead, New South Wales, Australia
- Grupo de Microbiología, Instituto Nacional de Salud, Bogotá, Colombia
| | - Luciana Trilles
- Molecular Mycology Research Laboratory, CIDM, Sydney Medical School - Westmead Hospital, The University of Sydney, Westmead Millennium Institute, Westmead, New South Wales, Australia
- Laboratório de Micologia, Instituto de Pesquisa Clínica Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Dumrongdej Piyabongkarn
- Mycology Laboratory, King Chulalongkorn Memorial Hospital, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Wijit Banlunara
- Department of Pathology, Faculty of Veterinary Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Natteewan Poonwan
- Mycology Laboratory, National Institute of Health, Nonthaburi, Thailand
| | - Angkana Chaiprasert
- Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Wieland Meyer
- Molecular Mycology Research Laboratory, CIDM, Sydney Medical School - Westmead Hospital, The University of Sydney, Westmead Millennium Institute, Westmead, New South Wales, Australia
| | - Ariya Chindamporn
- Mycology Laboratory, King Chulalongkorn Memorial Hospital, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- * E-mail:
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Cogliati M. Global Molecular Epidemiology of Cryptococcus neoformans and Cryptococcus gattii: An Atlas of the Molecular Types. SCIENTIFICA 2013; 2013:675213. [PMID: 24278784 PMCID: PMC3820360 DOI: 10.1155/2013/675213] [Citation(s) in RCA: 157] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 12/11/2012] [Indexed: 05/08/2023]
Abstract
Cryptococcosis is a fungal disease affecting more than one million people per year worldwide. The main etiological agents of cryptococcosis are the two sibling species Cryptococcus neoformans and Cryptococcus gattii that present numerous differences in geographical distribution, ecological niches, epidemiology, pathobiology, clinical presentation and molecular characters. Genotyping of the two Cryptococcus species at subspecies level supplies relevant information to understand how this fungus has spread worldwide, the nature of its population structure, and how it evolved to be a deadly pathogen. At present, nine major molecular types have been recognized: VNI, VNII, VNB, VNIII, and VNIV among C. neoformans isolates, and VGI, VGII, VGIII, and VGIV among C. gattii isolates. In this paper all the information available in the literature concerning the isolation of the two Cryptococcus species has been collected and analyzed on the basis of their geographical origin, source of isolation, level of identification, species, and molecular type. A detailed analysis of the geographical distribution of the major molecular types in each continent has been described and represented on thematic maps. This study represents a useful tool to start new epidemiological surveys on the basis of the present knowledge.
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Affiliation(s)
- Massimo Cogliati
- Lab. Micologia Medica, Dipartimento di Scienze Biomediche per la Salute, Università degli Studi di Milano, Via Pascal 36, 20133 Milano, Italy
- *Massimo Cogliati:
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Silva DC, Martins MA, Szeszs MW, Bonfietti LX, Matos D, Melhem MSC. Susceptibility to antifungal agents and genotypes of Brazilian clinical and environmental Cryptococcus gattii strains. Diagn Microbiol Infect Dis 2012; 72:332-9. [PMID: 22341512 DOI: 10.1016/j.diagmicrobio.2011.11.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Revised: 11/21/2011] [Accepted: 11/23/2011] [Indexed: 11/26/2022]
Abstract
There are few reports concerning the in vitro antifungal susceptibility of clinical and environmental Cryptococcus gattii isolates. In this study, we performed polymerase chain reaction-restriction fragment length polymorphism to investigate the molecular subtypes of 50 clinical and 4 environmental Brazilian isolates of C. gattii and assessed their antifungal susceptibility for fluconazole (FLU) and amphotericin B (Amb) according to recent recommendations proposed for antifungal susceptibility testing of nonfermentative yeasts. Time-kill curve studies were performed using RPMI 1640 medium to analyze the fungicidal effect of AmB. We found 47 VGII (94%) molecular types and 3 VGI (6%) types among the clinical isolates. The environmental isolates were VGII (75%) subtype and VGI (25%) subtype. The FLU-MIC ranged from 1 to 64 mg L(-1), and MIC(50)/MIC(90) values were, respectively, 8/16 mg L(-1). For AmB, the MICs were low and homogeneous, ranging from 0.12 to 0.5 mg L(-1), for VGI or VGII. The time required to reach the fungicidal end point (99.9% killing) was 6 h for the majority of strains (64%), but viable cells of VGII were still present after 48 h of exposition. We pointed out the occurrence of high FLU-MICs for C. gattii isolates with highest values for VGII. Our data also suggest that the rate of killing of C. gattii by AmB is strain dependent, and viable cells of VGII genotype strains were still observed after an extended incubation time, addressing future studies to determine whether the in vitro fungicidal activity could be clinically relevant.
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Affiliation(s)
- Dayane C Silva
- Mycology Unit of Adolfo Lutz Institute, Public Health Reference Laboratory, Secretary of Health, São Paulo-SP, 01246-902, Brazil
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14
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Iatta R, Hagen F, Fico C, Lopatriello N, Boekhout T, Montagna MT. Cryptococcus gattii Infection in an Immunocompetent Patient from Southern Italy. Mycopathologia 2011; 174:87-92. [DOI: 10.1007/s11046-011-9493-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 10/18/2011] [Indexed: 12/20/2022]
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15
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Clinical presentation, diagnosis and management of Cryptococcus gattii cases: Lessons learned from British Columbia. CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY 2011; 20:23-8. [PMID: 20190892 DOI: 10.1155/2009/719659] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2008] [Accepted: 09/05/2008] [Indexed: 01/24/2023]
Abstract
The environmental fungus Cryptococcus gattii emerged on Vancouver Island, British Columbia (BC), in 1999. By the end of 2006, it led to 176 cases and eight deaths - one of the highest burdens of C gattii disease worldwide. The present paper describes three cases, and the BC experience in the diagnosis and management of this infection. All three cases presented with pulmonary findings, including cryptococcomas and infiltrates. One also presented with brain cryptococcomas. Cases were diagnosed by chest and brain imaging, and laboratory evidence including serum or cerebrospinal fluid cryptococcal antigen detection and culture of respiratory or cerebrospinal fluid specimens. Genotyping of fungal isolates confirmed infection with C gattii VGIIa. Pulmonary cases were treated with fluconazole. One patient with central nervous system disease was treated with amphotericin B followed by fluconazole. Although this infection remains rare, clinicians should be aware of it in patients with a compatible clinical presentation who are either living in or returning from a trip to BC.
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16
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Jobbins SE, Hill CJ, D'Souza-Basseal JM, Padula MP, Herbert BR, Krockenberger MB. Immunoproteomic approach to elucidating the pathogenesis of cryptococcosis caused by Cryptococcus gattii. J Proteome Res 2010; 9:3832-41. [PMID: 20545298 DOI: 10.1021/pr100028t] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cryptococcosis caused by Cryptococcus gattii is a devastating disease of immunocompetent hosts with an incompletely understood pathogenesis. Utilizing an immunoproteomic approach in a naturally occurring koala model of disease, a number of key proteins and pathways are identified in the early and late pathogenesis of cryptococcosis for the first time. In particular, the thioredoxin system appears important in the pathogenesis of cryptococcosis caused by C. gattii VGII.
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Affiliation(s)
- Sarah E Jobbins
- The Faculty of Veterinary Science, the University of Sydney, Australia
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17
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Escandón P, Montilla A. Tipificación molecular de aislamientos del complejo Cryptococcus neoformans/Cryptococcus gattii. INFECTIO 2010. [DOI: 10.1016/s0123-9392(10)70130-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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18
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Sidrim JJC, Costa AKF, Cordeiro RA, Brilhante RSN, Moura FEA, Castelo-Branco DSCM, Neto MPDA, Rocha MFG. Molecular methods for the diagnosis and characterization of Cryptococcus: a review. Can J Microbiol 2010; 56:445-58. [PMID: 20657615 DOI: 10.1139/w10-030] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Cryptococcosis is a fungal infection caused by yeasts of the genus Cryptococcus, with Cryptococcus neoformans and Cryptococcus gattii as the primary pathogenic species. This disease is a threat to immunocompromised patients, especially those who have AIDS. However, the disease has also been described in healthy individuals. The tests used to identify these microorganisms have limitations that make final diagnosis difficult. However, currently there are specific gene sequences that can be used to detect C. neoformans and C. gattii from clinical specimens and cultures. These sequences can be used for identification, typing, and the study of population genetics. Among the main identification techniques are hybridization, which was the pioneer in molecular identification and development of specific probes for pathogen detection; PCR and other PCR-based methods, particularly nested PCR and multiplex PCR; and sequencing of specific genomic regions that are amplified through PCR, which is especially useful for diagnosis of cryptococcosis caused by unconventional Cryptococcus sp. Concerning microorganism typing, the following techniques have shown the best ability to differentiate between fungal serotypes and molecular types: PCR fingerprinting, PCR-RFLP, AFLP, and MLST. Thus, the accumulation of data generated by molecular methods can have a positive impact on monitoring resistant strains and treating diseases.
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Affiliation(s)
- José Júlio Costa Sidrim
- Specialized Medical Mycology Center, Federal University of Ceará, Rua Coronel Nunes de Melo, Rodolfo Teófilo, Fortaleza, Ceará, Brazil
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19
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Mora DJ, Pedrosa AL, Rodrigues V, Leite Maffei CM, Trilles L, Santos Lazéra MD, Silva-Vergara ML. Genotype and mating type distribution within clinicalCryptococcus neoformansandCryptococcus gattiiisolates from patients with cryptococcal meningitis in Uberaba, Minas Gerais, Brazil. Med Mycol 2010; 48:561-9. [DOI: 10.3109/13693780903358317] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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20
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Ferreira-Paim K, Andrade-Silva L, Mora DJ, Pedrosa AL, Rodrigues V, Silva-Vergara ML. Genotyping of Cryptococcus neoformans isolated from captive birds in Uberaba, Minas Gerais, Brazil. Mycoses 2010; 54:e294-300. [PMID: 20492533 DOI: 10.1111/j.1439-0507.2010.01901.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
To evaluate Cryptococcus spp. molecular types isolated from captive birds' droppings, an epidemiological survey was carried out in Uberaba, Minas Gerais, Brazil, from December 2006 to September 2008. A total of 253 samples of bird excreta (120 fresh and 133 dry) were collected from pet shop cages and houses in different neighbourhoods. Cryptococcus neoformans was isolated in 19 (14.28%) dry samples and one fresh sample (0.84%). Cryptococcus laurentii was recovered from seven (5.26%) dry samples, but not in the fresh samples. The canavanine-glycine-bromothymol blue test was positive in all but one of the C. laurentii isolates. Cryptococcus neoformans molecular typing was performed using URA5-RFLP and the mating type locus using mating type specific PCR. Nineteen (95.0%) presented genotype VNI and one VNII (5.0%). In addition, all isolates presented mating type α. Thus, the genotype of the environmental C. neoformans isolates observed in this study is in accordance with others already reported around the world and adds information about its distribution in Brazil. Cryptococcus laurentii strains were typed using URA5-RFLP and M13 fingerprinting, which showed similar profiles among them. Thus, despite the low number of C. laurentii isolates analysed, their molecular profile is different from another already reported.
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Affiliation(s)
- Kennio Ferreira-Paim
- Disciplina de Doenças Infecciosas Parasitárias, Universidade Federal do Triângulo Mineiro, Uberaba, Minas Gerais, Brazil
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21
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Meyer W, Aanensen DM, Boekhout T, Cogliati M, Diaz MR, Esposto MC, Fisher M, Gilgado F, Hagen F, Kaocharoen S, Litvintseva AP, Mitchell TG, Simwami SP, Trilles L, Viviani MA, Kwon-Chung J. Consensus multi-locus sequence typing scheme for Cryptococcus neoformans and Cryptococcus gattii. Med Mycol 2010; 47:561-70. [PMID: 19462334 DOI: 10.1080/13693780902953886] [Citation(s) in RCA: 339] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
This communication describes the consensus multi-locus typing scheme established by the Cryptococcal Working Group I (Genotyping of Cryptococcus neoformans and C. gattii) of the International Society for Human and Animal Mycology (ISHAM) using seven unlinked genetic loci for global strain genotyping. These genetic loci include the housekeeping genes CAP59,GPD1, LAC1, PLB1, SOD1, URA5 and the IGS1 region. Allele and sequence type information are accessible at http://www.mlst.net/ .
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Affiliation(s)
- Wieland Meyer
- Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Westmead Millennium Institute, University of Sydney Western Clinical School at Westmead Hospital, Westmead, Australia
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22
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Tekolo OM, Mckenzie J, Botha A, Prior BA. The osmotic stress tolerance of basidiomycetous yeasts. FEMS Yeast Res 2010; 10:482-91. [DOI: 10.1111/j.1567-1364.2010.00612.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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23
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Sudhadham M, de Hoog GS, Menken SBJ, Gerrits van den Ende AHG, Sihanonth P. Rapid screening for genotypes as possible markers of virulence in the neurotropic black yeast Exophiala dermatitidis using PCR-RFLP. J Microbiol Methods 2009; 80:138-42. [PMID: 19961882 DOI: 10.1016/j.mimet.2009.11.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2008] [Revised: 11/04/2009] [Accepted: 11/24/2009] [Indexed: 11/18/2022]
Abstract
A simple method for fungal genotype screening was developed for the black yeast Exophiala dermatitidis based on RFLP of ribosomal ITS regions currently used as potential virulence markers. In a study set of 502 strains of the species, two main genotypes were recognized. Only 0.97% of lanes were difficult to interpret as they did not clearly present one of the expected genotypes. Twenty strains were deviating and proved to be E. spinifera after sequencing. Eight common, related species (based on SSU data) with clinical significance yielded different patterns with TaqI digestion, and thus the method is also usable for routine diagnostics.
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Affiliation(s)
- M Sudhadham
- Centraalbureau voor Schimmelcultures Fungal Biodiversity Centre, Utrecht, The Netherlands
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24
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Genetic diversity of the Cryptococcus species complex suggests that Cryptococcus gattii deserves to have varieties. PLoS One 2009; 4:e5862. [PMID: 19517012 PMCID: PMC2690690 DOI: 10.1371/journal.pone.0005862] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Accepted: 05/13/2009] [Indexed: 01/02/2023] Open
Abstract
The Cryptococcus species complex contains two sibling taxa, Cryptococcus neoformans and Cryptococcus gattii. Both species are basidiomycetous yeasts and major pathogens of humans and other mammals. Genotyping methods have identified major haploid molecular types of C. neoformans (VNI, VNII, VNB and VNIV) and of C. gattii (VGI, VGII, VGIII and VGIV). To investigate the phylogenetic relationships among these haploid genotypes, we selected 73 strains from 2000 globally collected isolates investigated in our previous typing studies, representing each of these genotypes and carried out multigene sequence analyses using four genetically unlinked nuclear loci, ACT1, IDE, PLB1 and URA5. The separate or combined sequence analyses of all four loci revealed seven clades with significant support for each molecular type. However, three strains of each species revealed some incongruence between the original molecular type and the sequence-based type obtained here. The topology of the individual gene trees was identical for each clade of C. neoformans but incongruent for the clades of C. gattii indicating recent recombination events within C. gattii. There was strong evidence of recombination in the global VGII population. Both parsimony and likelihood analyses supported three major clades of C. neoformans (VNI/VNB, VNII and VNIV) and four major clades of C. gattii (VGI, VGII, VGIII and VGIV). The sequence variation between VGI, VGIII and VGIV was similar to that between VNI/VNB and VNII. MATa was for the first time identified for VGIV. The VNIV and VGII clades are basal to the C. neoformans or the C. gattii clade, respectively. Divergence times among the seven haploid monophyletic lineages in the Cryptococcus species complex were estimated by applying the hypothesis of the molecular clock. The genetic variation found among all of these haploid monophyletic lineages indicates that they warrant varietal status.
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25
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[In vitro determination of virulence factors activity associated with several Cryptococcus neoformans clinical isolates]. Rev Iberoam Micol 2009; 25:145-9. [PMID: 18785782 DOI: 10.1016/s1130-1406(08)70034-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Different phenotypic characteristics associated with virulence of the Cryptococcus neoformans species complex have shown an important role in their pathogenicity. In this study we have determined the role of phenotypically and genotypically factors of some virulence factors from clinical isolates in the two species of the complex; 35 C. neoformans and 19 Cryptococcus gattii. Growth at 37 degrees C, macroscopic and microscopic morphology, switching phenomenon, activity of 23 extracellular enzymes, variability of the colonies in agar with phloxin B; phospholipase B gene, and the mating type were determined by PCR; the molecular pattern was determined by URA5 RFLP. All isolates grew at 37 degrees C, the capsular size was greater in C. gattii (1.87 microm -/+1.47 microm) than in C. neoformans (0.83 microm -/+0.15 microm). Switching was observed mainly in isolates of C. gattii. All isolates expressed the enzyme urease, a lower activity of the proteases (Pz= 0.54), but a higher activity of the phospholipase (Pz=0.43) and phenoloxidase (Pz=0.003) was determined for C. gattii.
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26
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Feng X, Yao Z, Ren D, Liao W. Simultaneous identification of molecular and mating types within the Cryptococcus species complex by PCR-RFLP analysis. J Med Microbiol 2009; 57:1481-1490. [PMID: 19018017 DOI: 10.1099/jmm.0.2008/003665-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The Cryptococcus species complex consists of two species, Cryptococcus neoformans and Cryptococcus gattii, which cause systemic infections in both immunocompromised and immunocompetent patients. Both species have a bipolar mating system, with mating type (MAT) alpha being predominant in clinical and environmental isolates. The strains of the Cryptococcus species complex have been divided into eight major molecular types, which show differences in epidemiology, biology and pathogenicity. In this study, two PCR-RFLP analyses, based on the CAP1 and GEF1 genes, which are both located at the MAT locus, were developed for simultaneous identification of the molecular and mating types of isolates of the Cryptococcus species complex. The molecular and mating types of all 144 cryptococcal isolates, including rare subtypes, were successfully determined by both PCR-RFLP approaches. Pattern analysis of the AD hybrids revealed that the serotype A MATa allele in strains of AaDalpha derived from genotype VNB, whereas the serotype A MATalpha allele among strains of AalphaDa and AalphaDalpha derived from molecular type VNI.
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Affiliation(s)
- Xiaobo Feng
- Medical Mycology Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, PR China
| | - Zhirong Yao
- Medical Mycology Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, PR China
| | - Daming Ren
- State Key Laboratory of Genetic Engineering, Institute of Genetics, Fudan University, Shanghai, PR China
| | - Wanqing Liao
- Medical Mycology Laboratory, Shanghai Changzheng Hospital, Shanghai, PR China
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27
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Kaocharoen S, Wang B, Tsui KM, Trilles L, Kong F, Meyer W. Hyperbranched rolling circle amplification as a rapid and sensitive method for species identification within the Cryptococcus species complex. Electrophoresis 2008; 29:3183-91. [PMID: 18600831 DOI: 10.1002/elps.200700903] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The Cryptococcus species complex contains two closely related basidiomycetous yeasts: Cryptococcus neoformans and C. gattii, which cause cryptococcosis in humans and other animals. The species and varieties are characterized, by different clinical, epidemiological, biochemical and molecular features. The currently used identification methods are either time-consuming or not anymore commercially available. However, a rapid, sensitive and robust assay for the detection of these pathogens is vital for early diagnosis and appropriate treatment decisions. To overcome those limitations, four padlock probes targeting species-specific single nucleotide polymorphisms at the internal transcribed spacers (ITSs) of the RNA gene locus were developed and applied during isothermal hyperbranched rolling circle amplification (HRCA). The probes were tested against 99 samples, including 94 clinical cryptococcal cultures, three closely related Cryptococcus species, and two clinical specimens. The use of the padlock probes and the combination of probe signal amplification by HRCA provided a quick and sensitive assay for the accurate identification of C. neoformans var. grubii, C. neoformans var. neoformans and C. gattii. HRCA was also useful to detect hybrids, when they were heterozygous at the ITS locus. The HRCA results were in agreement with previous genotyping data based on PCR fingerprinting, amplified fragment length polymorphism and ITS sequencing.
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Affiliation(s)
- Sirada Kaocharoen
- Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Westmead Millennium Institute, Westmead Hospital, Westmead, Australia
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28
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Trilles L, Lazéra MDS, Wanke B, Oliveira RV, Barbosa GG, Nishikawa MM, Morales BP, Meyer W. Regional pattern of the molecular types of Cryptococcus neoformans and Cryptococcus gattii in Brazil. Mem Inst Oswaldo Cruz 2008; 103:455-62. [PMID: 18797758 DOI: 10.1590/s0074-02762008000500008] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2008] [Accepted: 07/09/2008] [Indexed: 11/22/2022] Open
Abstract
The molecular types of 443 Brazilian isolates of Cryptococcus neoformans and Cryptococcus gattii were analyzed to determine their geographic distribution within Brazil and their underlying host conditions. The following data, imported from previous epidemiological studies as well as two culture collections, were analyzed for: place of isolation, source (clinical or environmental), host risk factors, species, serotype, mating type, and molecular type. Molecular typing by PCR-fingerprinting using primers for the minisatellite-specific core sequence of the wild-type phage M13 or microsatellites [(GACA)4, (GTG)5], restriction fragment length polymorphism of URA5 gene analysis, and/or amplified fragment length polymorphism (AFLP) identified eight major genotypes: VNI/AFLP1, VNII/AFLP1A, VNIII/AFLP2, and VNIV/AFLP3 for C. neoformans, and VGI/AFLP4, VGII/AFLP6, VGIII/AFLP5, and VGIV/AFLP7 for C. gattii. The most common molecular type found in Brazil was VNI (64%), followed by VGII (21%), VNII (5%), VGIII (4%), VGI and VNIV (3% each), and VNIII (< 1%). Primary cryptococcosis caused by the molecular type VGII (serotype B, MAT alpha) prevails in immunocompetent hosts in the North and Northeast regions, disclosing an endemic regional pattern for this specific molecular type in the Northern Brazil.
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Affiliation(s)
- Luciana Trilles
- Molecular Mycology Research Laboratory, Center for Infectious Diseases and Microbiology, Westmead Hospital, Westmead Millennium Institute, Western Clinical School, University of Sydney, Sydney, Austrália.
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29
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Six monophyletic lineages identified within Cryptococcus neoformans and Cryptococcus gattii by multi-locus sequence typing. Fungal Genet Biol 2008; 45:400-21. [DOI: 10.1016/j.fgb.2007.12.004] [Citation(s) in RCA: 146] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2007] [Revised: 12/06/2007] [Accepted: 12/10/2007] [Indexed: 12/17/2022]
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30
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Diversidad del complejo de especies Cryptococcus neoformans-Cryptococcus gattii. Rev Iberoam Micol 2008; 25:S4-12. [DOI: 10.1016/s1130-1406(08)70019-6] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
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31
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Hanafy A, Kaocharoen S, Jover-Botella A, Katsu M, Iida S, Kogure T, Gonoi T, Mikami Y, Meyer W. Multilocus microsatellite typing forCryptococcus neoformansvar.grubii. Med Mycol 2008; 46:685-96. [DOI: 10.1080/13693780802027062] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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32
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Raimondi A, Ticozzi R, Sala G, Bellotti MG. Genotype-based differentiation of the Cryptococcus neoformans serotypes by combined PCR-RFLP analysis of the capsule-associated genes CAP10 and CAP59. Med Mycol 2007; 45:491-501. [PMID: 17710618 DOI: 10.1080/13693780701397681] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
This report describes an indirect identification method for Cryptococcus neoformans serotypes developed using combined restriction enzyme pattern analysis of two PCR-amplified portions of the capsule-associated genes CAP10 and CAP59. The method relies on the recognition of the sequence conformation of nine serotype-related polymorphic sites by the analysis of four restriction profiles. A 610 nucleotides long trait of the CAP10 gene was digested with the enzymes Sty I or Sal I and a 597 nucleotides long trait of the CAP59 gene was digested with the enzymes Sal I or EcoRV+PstI. The resulting profiles, reported as a string of four numbers, defined for each strain an intrinsically coherent allelic profile closely correlated to the serotype. We analyzed by this method 172 C. neoformans strains obtained from different sources. All the serotype A strains examined and all the strains of the B-C serotypes group were recognized by specific allelic profiles, but serotypes B and C could not be distinguished from each other. Of the serotype D strains, 84% were characterized by a unique allelic pattern, while the remaining 16% were genotypically indistinguishable from the AD serotype organisms among which differences in the ploidy number and evidence of recombination could be recognized.
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Affiliation(s)
- Alessandro Raimondi
- Dipartimento di Sanità Pubblica, Microbiologia, Virologia, Università degli Studi di Milano, Milano, Italy.
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Bovers M, Diaz MR, Hagen F, Spanjaard L, Duim B, Visser CE, Hoogveld HL, Scharringa J, Hoepelman IM, Fell JW, Boekhout T. Identification of genotypically diverse Cryptococcus neoformans and Cryptococcus gattii isolates by Luminex xMAP technology. J Clin Microbiol 2007; 45:1874-83. [PMID: 17442792 PMCID: PMC1933031 DOI: 10.1128/jcm.00223-07] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2007] [Revised: 03/05/2007] [Accepted: 04/11/2007] [Indexed: 11/20/2022] Open
Abstract
A Luminex suspension array, which had been developed for identification of Cryptococcus neoformans and Cryptococcus gattii isolates, was tested by genotyping a set of 58 mostly clinical isolates. All genotypes of C. neoformans and C. gattii were included. In addition, cerebrospinal fluid (CSF) obtained from patients with cryptococcal meningitis was used to investigate the feasibility of the technique for identification of the infecting strain. The suspension array correctly identified haploid isolates in all cases. Furthermore, hybrid isolates possessing two alleles of the Luminex probe region could be identified as hybrids. In CSF specimens, the genotype of the cryptococcal strains responsible for infection could be identified after optimization of the PCR conditions. However, further optimization of the DNA extraction protocol is needed to enhance the usability of the method in clinical practice.
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Affiliation(s)
- M Bovers
- CBS-Fungal Biodiversity Centre, Uppsalalaan 8, NL-3584CT Utrecht, The Netherlands
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34
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Matsumoto MT, Fusco-Almeida AM, Baeza LC, Melhem MDSC, Medes-Giannini MJS. Genotyping, serotyping and determination of mating-type of Cryptococcus neoformans clinical isolates from São Paulo State, Brazil. Rev Inst Med Trop Sao Paulo 2007; 49:41-7. [PMID: 17384819 DOI: 10.1590/s0036-46652007000100008] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2006] [Accepted: 08/16/2006] [Indexed: 11/22/2022] Open
Abstract
The basidiomycetous yeast Cryptococcus neoformans is an important fungal pathogen mainly in immunocompromised patients. In this study, 47 clinical isolates of C. neoformans from regions of São Paulo State were studied serologically by using the Crypto Check Iatron RM 304-K kit, their genetic diversity was estimated by PCR-fingerprinting with a microsatellite-specific sequence (GACA)4, RAPD with primer 6 (Amersham Pharmacia Biotech), PCR-restriction fragment length polymorphism (RFLP) analysis of the phospholipase B gene (PLB1) digested with AvaI and mating type analysis by PCR. All 47 strains isolated from HIV positive patients included in this study were serotype A and MATalpha. The majority of the isolates (45/47) were VNI and only two were VNII by PCR-fingerprinting and PCR-RFLP analysis. High degree of homogeneity was observed when (GACA)4 was used, being highly correlated (> 0.9). In contrast, the RAPD analysis was more heterogeneous with higher number of molecular profiles. By PCR-RFLP, no new molecular type was found, enhancing the suggestion that the differences based on conserved gene as PLB1, can be resultant of ongoing divergent evolution within the C. neoformans complex, into the current eight subtypes. Our results furnish new information on the molecular epidemiology of C. neoformans in the southeast region of Brazil.
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Affiliation(s)
- Marcelo Teruyuki Matsumoto
- Departamento de Análises Clínicas, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP, Brasil
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Bovers M, Hagen F, Kuramae EE, Diaz MR, Spanjaard L, Dromer F, Hoogveld HL, Boekhout T. Unique hybrids between the fungal pathogens Cryptococcus neoformans and Cryptococcus gattii. FEMS Yeast Res 2006; 6:599-607. [PMID: 16696655 DOI: 10.1111/j.1567-1364.2006.00082.x] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Cryptococcus neoformans and Cryptococcus gattii are yeasts that cause meningoencephalitis, but that differ in host range and geographical distribution. Cryptococcus neoformans occurs world-wide and mostly infects immunocompromised patients, whereas C. gattii occurs mainly in (sub)tropical regions and infects healthy individuals. Anomalous C. neoformans strains were isolated from patients. These strains were found to be monokaryotic, and diploid or aneuploid. Amplified Fragment Length Polymorphism (AFLP) and sequence analyses indicated that AFLP genotypes 2 (C. neoformans) and 4 (C. gattii) were present. The strains were serologically BD. Mating- and serotype-specific PCR reactions showed that the strains were MATa-serotype D/MATalpha-serotype B. This study is the first to describe naturally occurring hybrids between C. neoformans and C. gattii.
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Affiliation(s)
- Marjan Bovers
- CBS-Centraalbureau voor Schimmelcultures, Utrecht, the Netherlands
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Escandón P, Sánchez A, Martínez M, Meyer W, Castañeda E. Molecular epidemiology of clinical and environmental isolates of the Cryptococcus neoformans species complex reveals a high genetic diversity and the presence of the molecular type VGII mating type a in Colombia. FEMS Yeast Res 2006; 6:625-35. [PMID: 16696659 DOI: 10.1111/j.1567-1364.2006.00055.x] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The aim of this study was to investigate the epidemiological relationships of clinical and environmental isolates of the Cryptococcus neoformans species complex in Colombia. The current study reflects data from 1987 to 2004. In Colombia serotypes A and B are most frequently recovered from patients and the environment. Of the 178 clinical isolates studied, 91.1% were of serotype A, 8.4% serotype B and 0.5% serotype C. Of the 247 environmental isolates, 44.2% were of serotype A, 42.6% serotype B and 13.2% serotype C. No serotype D isolates were isolated. Serotype AD has not been recovered in Colombia. PCR fingerprinting with the primers M13, (GACA)4 and (GTG)5 and URA5 gene restriction fragment length polymorphism analysis grouped the majority of clinical serotype A and environmental serotype B isolates into the molecular types VNI (98.1%) and VGII (100%), respectively. Mating type alpha was determined in 99.3% of serotype A isolates, but 96.6% of serotype B isolates were of mating type a. Similar profiles between clinical and environmental isolates suggest that the patients may have acquired the infection from the environment. The data presented form part of the Colombian contribution to the ongoing global survey of the C. neoformans species complex.
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Affiliation(s)
- Patricia Escandón
- Grupo de Microbiología, Instituto Nacional de Salud, Bogotá, Colombia
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Granados DP, Castañeda E. Influence of climatic conditions on the isolation of members of theCryptococcus neoformansspecies complex from trees in Colombia from 1992â2004. FEMS Yeast Res 2006; 6:636-44. [PMID: 16696660 DOI: 10.1111/j.1567-1364.2006.00090.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The aim of this retrospective study was to analyze the relationship between occurrence of the serotypes of the Cryptococcus neoformans species complex in tree samples and the climatic conditions registered during samplings in four cities of Colombia, between 1992 and 2004, by means of a logistic regression model and lagged Pearson correlations. During 97 collection dates, 8220 samples from different tree species were taken, of which 2.63% were positive: 56.5% yielded serotype B, 24.7% serotype C and 18.8% serotype A isolates. The prevalence of the serotypes varied among the cities. The results suggest that environmental climatic conditions, mainly humidity, temperature, evaporation and solar radiation, can affect the occurrence of the different serotypes in trees in a differential manner. These different climatic tolerances were reflected in the geographic distribution of the serotypes in Colombia. The climatic conditions for 15 days before the sampling date were correlated with positive or negative isolation of the different serotypes.
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Spiegel IB, White SD, Foley JE, Drazenovich NL, Ihrke PJ, Affolter VK. A retrospective study of cutaneous equine sarcoidosis and its potential infectious aetiological agents. Vet Dermatol 2006; 17:51-62. [PMID: 16412120 DOI: 10.1111/j.1365-3164.2005.00494.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Nine horses from ages 5 to 21 years were diagnosed with cutaneous equine sarcoidosis (ES) over an 18-year period. In addition to skin, the lungs were frequently involved, with other organ systems affected less commonly. A predisposition for thoroughbreds and geldings was noted. Cutaneous lesions and signs included crusts, scales, alopecia and pruritus. These were found at various sites, particularly the legs/thighs/elbows, thorax, neck, face and ventral abdomen. Three horses were euthanized shortly after hospitalization; others survived as long as 12 years. Histopathologic stains, immunohistochemistry and polymerase chain reaction assays on paraffin-embedded cutaneous specimens from eight horses for Mycobacterium spp., Coccidioides immitis, Cryptococcus neoformans, Corynebacterium pseudotuberculosis, and Borrelia burgdorferi were all negative. The aetiology of ES is unlikely microbial and continues to be a diagnosis of exclusion. ES, when limited to the skin, is associated with a good prognosis, with either partial or complete response to glucocorticoid therapy in all the surviving horses.
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Affiliation(s)
- Ian B Spiegel
- Veterinary Medical Teaching Hospital, University of California, Davis, California 95616, USA.
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Diaz MR, Boekhout T, Kiesling T, Fell JW. Comparative analysis of the intergenic spacer regions and population structure of the species complex of the pathogenic yeast. FEMS Yeast Res 2005; 5:1129-40. [PMID: 16061425 DOI: 10.1016/j.femsyr.2005.05.005] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2005] [Revised: 04/18/2005] [Accepted: 05/03/2005] [Indexed: 12/16/2022] Open
Abstract
Cryptococcus neoformans is an opportunistic basidiomycete responsible for the high incidence of cryptococcosis in patients with AIDS and in other immune-compromised individuals. This study, which focused on the molecular structure and genetic variability of the two varieties in the C. neoformans and Cryptococcus gattii species complex, employed sequence analysis of the intergenic spacer regions, IGSI and IGSII. The IGS region is the most rapidly evolving region of the rDNA families. The IGSI displayed the most genetic variability represented by nucleotide base substitutions and the presence of long insertions/deletions (indels). In contrast, the IGSII region exhibited less heterogeneity and the indels were not as extensive as those displayed in the IGSI region. Both intergenic spacers contained short, interspersed repeat motifs, which can be related to length polymorphisms observed between sequences. Phylogenetic analysis undertaken in the IGSI, IGSII and IGSI +5S rRNA + IGSII regions revealed the presence of six major phylogenetic lineages, some of which segregated into subgroups. The major lineages are represented by genotypes 1 (C. neoformans var. grubii), genotype 2 (C. neoformans var. neoformans), and genotypes 3, 4, 5 and 6 represented by C. gattii. Genotype 6 is a newly described IGS genotypic group within the C. neoformans species complex. With the inclusion of IGS subgenotypic groups, our sequence analysis distinguished 12 different lineages. Sequencing of clones, which was performed to determine the presence of multiple alleles at the IGS locus in several hybrid strains, yielded a single IGS sequence type per isolate, thus suggesting that the selected group of cloned strains was mono-allelic at this locus. IGS sequence analyses proved to be a powerful technique for the delineation of the varieties of C. neoformans and C. gattii at genotypic and subgenotypic levels.
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Affiliation(s)
- Mara R Diaz
- Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Key Biscayne, FL 33149, USA.
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Diaz MR, Fell JW. Use of a suspension array for rapid identification of the varieties and genotypes of the Cryptococcus neoformans species complex. J Clin Microbiol 2005; 43:3662-72. [PMID: 16081894 PMCID: PMC1233893 DOI: 10.1128/jcm.43.8.3662-3672.2005] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Cryptococcus neoformans is an encapsulated fungal pathogen known to cause severe disease in immunocompromised patients. The disease, cryptococcosis, is mostly acquired by inhalation and can result in a chronic meningoencephalitis, which can be fatal. Here, we describe a molecular method to identify the varieties and genotypic groups within the C. neoformans species complex from culture-based assays. The method employs a novel flow cytometer with a dual laser system that allows the simultaneous detection of different target sequences in a multiplex and high-throughput format. The assay uses a liquid suspension hybridization format with specific oligonucleotide probes that are covalently bound to the surface of fluorescent color-coded microspheres. Biotinylated target amplicons, which hybridized to their complementary probe sequences, are quantified by the addition of the conjugate, streptavidin R-phycoerythrin. In this study we developed and validated eight probes derived from sequence analysis of the intergenic spacer region of the rRNA gene region. The assay proved to be specific and sensitive, allowed discrimination of a 1-bp mismatch with no apparent cross-reactivity, and detected 10(1) to 10(3) genome copies. The described protocol, which can be used directly with yeast cells or isolated DNA, can be undertaken in less than 1 h following PCR amplification and permits identification of species in a multiplex format. In addition to a multiplex capability, the assay allows the simultaneous detection of target sequences in a single reaction. The accuracy, speed, flexibility, and sensitivity of this technology are a few of the advantages that will make this assay useful for the diagnosis of human cryptococcal infections and other pathogenic diseases.
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Affiliation(s)
- Mara R Diaz
- Division of Marine Biology and Fisheries, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL 33149, USA.
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Butler MI, Poulter RTM. The PRP8 inteins in Cryptococcus are a source of phylogenetic and epidemiological information. Fungal Genet Biol 2005; 42:452-63. [PMID: 15809009 DOI: 10.1016/j.fgb.2005.01.011] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2004] [Revised: 01/20/2005] [Accepted: 01/25/2005] [Indexed: 11/17/2022]
Abstract
Only two nuclear encoded inteins have been described. The first, SceVMA, was found in a vacuolar ATPase gene of Saccharomyces cerevisiae and related yeasts. The second, CnePRP8, was found in the PRP8 gene of Cryptococcus neoformans. CnePRP8 contains protein sequences associated with intein splicing but no endonuclease domain. We compared allelic mini-inteins in both varieties of C. neoformans (var. neoformans and var. grubii) and in the related primary pathogen C. gattii to study the evolution of both the mini-intein and the host. We also describe a full-length, endonuclease-containing intein in Cryptococcus laurentii, a moderately distant relation of C. neoformans. We did not detect an intein in the PRP8 gene of other species of Cryptococcus including species closely related to the C. neoformans/C. gattii group. It is therefore probable that the C. neoformans/C. gattii mini-intein was derived from horizontal transfer in which C. laurentii or another intein-containing species was the source.
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Affiliation(s)
- Margaret I Butler
- Department of Biochemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand.
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Current awareness on yeast. Yeast 2003; 20:1007-14. [PMID: 14587515 DOI: 10.1002/yea.948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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