Structural studies of mannans from Candida albicans (serotypes A and B), Candida parapsilosis, Candida stellatoidea, and Candida tropicalis

1967 ◽  
Vol 45 (19) ◽  
pp. 2205-2211 ◽  
Author(s):  
R. J. Yu ◽  
C. T. Bishop ◽  
F. P. Cooper ◽  
H. F. Hasenclever ◽  
F. Blank

Mannans have been isolated from cells of the following Candida species: C. albicans (serotype A), C. albicans (serotype B), C. parapsilosis, C. stellatoidea, and C. tropicalis. Methylation and hydrolysis of each mannan yielded the following methyl ethers of d-mannose (with only small variations in the relative amounts): 2,3,4,6-tetra-O-methyl-d-mannose, 3,4,6-tri-O-methyl-d-mannose (major), 2,3,4-tri-O-methyl-d-mannose (minor), 2,4,6-tri-O-methyl-d-mannose (minor), 3,4-di-O-methyl-d-mannose, and 3,5-di-O-methyl-d-mannose. The mannans therefore contained a predominance of 1 → 2 linkages in the linear portions, with smaller amounts of 1 → 6 and 1 → 3 linkages. Branching occurred through C-2 and C-6 of d-mannopyranose and d-mannofuranose units, and branches were terminated by d-mannopyranose units. The specific rotations of the mannans indicated that most of the glycosidic linkages were in the α configuration. The structural studies support the observation that the mannans are very similar serologically and show cross-reactivity in antisera to any of the parent organisms.

Author(s):  
Joachim Ohiakwu Ezeadila ◽  
Ikechukwu Okoli ◽  
Christie Amaechi Oyeka

There is an increase in non-albicans Candida (NAC) vulvovaginal candidiasis which is attributed to overuse of antifungal therapy and this has led to antifungal resistance. This study was aimed at determining the antifungal resistance pattern of some clinical isolates of Candida species. Eighty-eight (88) isolates were used which included Candida tropicalis (34), Candida Parapsilosis (21), Candida albicans (20), Candida krusei (7) and Candida glabrata (6). The drugs used were Fluconazole (25µg), Ketoconazole (10µg), Voriconazole (1µg), Nystatin (100Units), Amphotericin B (20µg), Flucytosine (1µg), Clotrimazole (10µg) and Itraconazole (50µg). The susceptibility testing was carried out using the M44-A standard method for yeast disk diffusion testing. Results showed that the percentages of Candida species resistant to Fluconazole, Ketoconazole, Voriconazole, Amphotericin B, Flucytosine, Clotrimazole and Itraconazole and Nystatin were 52.3%, 61.9%, 35.2%, 19.3%, 86.4%, 34.1%,  45.5% and 44.3%,  with inhibition zone diameters ≤14mm, ≤20mm, ≤13mm, <10mm, ≤11mm, ≤11mm, ≤13mm and no inhibition zone diameter respectively. Candida krusei was the most resistant species with 100% resistance to each of Fluconazole, Ketoconazole and Flucytosine. Candida tropicalis was the species with the highest susceptibility (79.4%) to Amphotericin B followed by Candida parapsilosis with inhibition zone diameters ≥15mm. While Candida glabrata showed 100% resistance to each of Flucytosine and Itraconazole, Candida albicans showed 100% resistance to Flucytosine only. Candida glabrata was the only Candida species with 0% resistance to Amphotericin B. The drug to which most of the Candida species were susceptible was Amphotericin B followed by Voriconazole while Flucytosine was the drug with the highest resistance followed by Ketoconazole and Fluconazole. The highest number of susceptible-dose dependent Candida isolates was observed with Ketoconazole (25%), followed by Clotrimazole and Itraconazole, each recording 23.9%. Based on the findings of the present study, Voriconazole is recommended for vaginal candidiasis especially in the study area and also especially for infections caused by Fluconazole-resistant Candida species. This suggests that routine sensitivity testing is pertinent to guiding the choice of antifungal therapy. Thus, indiscriminate use of antifungal drugs should be avoided to reduce the development and spread of resistance.


2021 ◽  
Vol 36 (3) ◽  
pp. 79-84
Author(s):  
Hardi Hutabarat ◽  
Ida B. E. U. Wija Wija ◽  
Forman E. Siagian ◽  
Retno Wahyuningsih

AbstrakMikrobiota terbesar pada tubuh manusia terdapat pada saluran cerna (70%).Mikrobiota normal saluran cerna tersusun atas komposisi mikroorganisme yang unik dan berada dalam keadaan seimbang, didalamnya termasuk Candidaspp., yang hidup sebagai komensal. Data tentang keberadaan Candida dalam usus terutama berasal dari orang dewasa, sedangkan data pada anak sangat jarang. Penelitian ini bertujuan untuk mengetahui keragaman spesies Candida dan bebannya pada saluran cerna anak. Untuk menghitung beban jamur, sebanyak 0,2 g tinja ditanam pada agar sabouraud dekstrosa (ASD). Beban jamur dihitung berdasarkan koloni yang tumbuh dan disesuaikan menjadi per gram tinja (colony forming unit – CFU/g tinja). Identifikasi Candida dilakukan berdasarkan koloni yang tumbuh pada medium CHROMagar Candida (Paris, France). Populasi penelitian adalah anak umur 0-18 tahun (sesuai kriteria WHO). Sampel berasal dari RT 10 dan 11, Kampung Pluis, Jakarta Selatan dan RT 4, 6 dan 9, Kelurahan Cawang. Sebanyak 61 sampel tinja ditanam pada medium, dan didapat 72 isolat dari 43 pertumbuhan yang berasal dari 54 anak sehat dan tujuh anak sakit, yang dirawat di Departemen Kesehatan Anak RS UKI dengan berbagai sebab. Isolat yang didapat terdiri atas Candida tropicalis, Candida albicans, Candida parapsilosis, dan Candida glabrata. Beban jamur 1-50 CFU ditemukan pada 18 pasien, diikuti oleh beban jamur 151-200 CFU pada tujuh pasien. Selain itu, ditemukan infeksi campuran (dua spesies) pada sembilan sampel dan 3 spesies pada tujuh sampel. Tinja anak sakit didominasi C. tropicalis, empat sampel memiliki campuran C. tropicalis dengan C. albicans, dan C. tropicalis dengan C. parapsilosis. Kata Kunci: Candida, spesies, CFU, beban jamurCandida Load in the Children’s Gastrointestinal TractAbstractThe largest microbiota in the human body is found in the digestive tract (70%). The microbiota in the digestive tract is normally composed of a unique composition of microorganisms and is in a balanced state, including Candida spp., which live as commensals. Data on the presence of Candida in the intestine, especially coming from an adult, while the data in children are very rare. This study aims to determine the diversity of Candida species and fungal burden on the children’s digestive tract. To calculate the fungal load, 0.2g of faeces were planted on sabouraud dextrose agar (ASD). The fungal load was calculated based on the growing colonies and adjusted to be per gram of faeces (colony forming unit - CFU/g of faeces). Candida identification was carried out based on the colonies that grew on the CHROMagar Candida medium (Paris, France). The study population was children aged 0-18 years (according to WHO criteria). Samples came from RT 10 and 11, KampungPluis, South Jakarta and RT 4, 6 and 9, Cawang. A total of 61 stool samples were planted on the medium, and obtained 72 isolates from 43 growths from 54 healthy children and seven children who were treated at the Children’s Health Department of UKI Hospital for various reasons. The isolates obtained consisted of Candida tropicalis, Candida albicans, Candida parapsilosis, and Candida glabrata. 1-50 CFU fungal burden was found in 18 patients, followed by 151-200 CFU fungal burden in seven patients. In addition, there were mixed infections (two species) in nine samples and three species in seven samples. The stool of the sick children was predominantly C. tropicalis, four samples had a mixture of C. tropicalis with C. albicans, and C. tropicaliswith C. parapsilosis.Keywords: Candida, species, CFU, fungal burden


2009 ◽  
Vol 42 (2) ◽  
pp. 188-191 ◽  
Author(s):  
Danielle Patrícia Cerqueira Macêdo ◽  
Aline Mary de Almeida Farias ◽  
Reginaldo Gonçalves de Lima Neto ◽  
Vanessa Karina Alves da Silva ◽  
André Ferraz Goiana Leal ◽  
...  

Infecções por leveduras são freqüentes em imunocomprometidos, contudo espécies emergentes têm alterado o perfil epidemiológico. A habilidade de secretar proteases tem sido associada à patogenicidade do gênero Candida. Esta pesquisa teve como objetivos diagnosticar leveduroses em pacientes imunocomprometidos e avaliar a virulência dos agentes etiológicos baseado em teste de secreção de protease utilizando soro de albumina bovina como substrato. Do total de 104 pacientes estudados, 19 apresentaram episódios de leveduroses. O trato respiratório (63,2%), seguido pelo trato urinário (10,5%) foram os locais mais comuns de infecção. Candida albicans, Candida parapsilosis, Candida tropicalis e espécies emergentes como Candida krusei e Candida guilliermondii foram isoladas. Cinco isolados de Candida parapsilosis e um de Candida albicans e Candida guilliermondii exibiram alta atividade enzimática. Concluímos que a caracterização enzimática de isolados de Candida pode ser um útil marcador prognóstico, especialmente em imunocomprometidos, uma vez que leveduroses nestes pacientes são geralmente graves.


2020 ◽  
Vol 66 (6) ◽  
pp. 377-388
Author(s):  
Jonathas Sales de Oliveira ◽  
Vandbergue Santos Pereira ◽  
Débora de Souza Collares Maia Castelo-Branco ◽  
Rossana de Aguiar Cordeiro ◽  
José Júlio Costa Sidrim ◽  
...  

Candida tropicalis is a prominent non-Candida albicans Candida species involved in cases of candidemia, mainly causing infections in patients in intensive care units and (or) those presenting neutropenia. In recent years, several studies have reported an increase in the recovery rates of azole-resistant C. tropicalis isolates. Understanding C. tropicalis resistance is of great importance, since resistant strains are implicated in persistent or recurrent and breakthrough infections. In this review, we address the main mechanisms underlying C. tropicalis resistance to the major antifungal classes used to treat candidiasis. The main genetic basis involved in C. tropicalis antifungal resistance is discussed. A better understanding of the epidemiology of resistant strains and the mechanisms involved in C. tropicalis resistance can help improve diagnosis and assessment of the antifungal susceptibility of this Candida species to improve clinical management.


Biochemistry ◽  
1994 ◽  
Vol 33 (32) ◽  
pp. 9791-9799 ◽  
Author(s):  
Martin Fusek ◽  
Elizabeth A. Smith ◽  
Michael Monod ◽  
Ben M. Dunn ◽  
Stephen I. Foundling

1967 ◽  
Vol 45 (19) ◽  
pp. 2264-2267 ◽  
Author(s):  
R. J. Yu ◽  
C. T. Bishop ◽  
F. Blank ◽  
H. F. Hasenclever

2010 ◽  
Vol 43 (6) ◽  
pp. 673-677 ◽  
Author(s):  
Olivia Cometti Favalessa ◽  
Marilena dos Anjos Martins ◽  
Rosane Christine Hahn

INTRODUÇÃO: A candidíase é uma das infecções fúngicas mais frequentes entre os pacientes infectados pelo vírus da imunodeficiência humana. O presente estudo objetivou a caracterização das leveduras do gênero Candida de distintas amostras clínicas, provenientes de pacientes HIV - positivos, assim como a determinação do perfil de suscetibilidade in vitro a cinco drogas antifúngicas. MÉTODOS: A caracterização dos isolados de Candida sp foi realizada através da metodologia clássica, testes bioquímicos (zimograma e auxanograma) e morfológicos (prova do tubo germinativo e microcultivo em lâmina). Também, foram realizadas a técnica genotípica (PCR) e identificação pelo método comercial API 20C AUX (BioMeriéux). Para a determinação do perfil de suscetibilidade in vitro, foram utilizadas cinco drogas antifúngicas (cetoconazol, fluconazol, itraconazol, voriconazol e anfotericina B), através do método comercialmente disponível - Etest. RESULTADOS: Foram identificados 105 isolados de leveduras do gênero Candida provenientes de 102 pacientes infectados pelo vírus HIV. Destes, foram caracterizadas 82 (78,1%) Candida albicans, 8 (7,6%) Candida parapsilosis, 8 (7,6%) Candida tropicalis, 4 (3,8%) Candida krusei, 2 (1,9%) Candida glabrata e 1 (1%) Candida guilliermondii. CONCLUSÕES: Considerando o perfil geral de sensibilidade, 60% dos isolados foram suscetíveis a todos os antifúngicos testados, porém as espécies C. tropicalis e C. krusei demonstraram uma tendência a valores mais elevados de CIMs para os azóis do que os encontrados paraC. albicans, sugerindo resistência.


2004 ◽  
Vol 72 (1) ◽  
pp. 209-218 ◽  
Author(s):  
Thomas R. Kozel ◽  
Randall S. MacGill ◽  
Ann Percival ◽  
Qing Zhou

ABSTRACT Sera from normal adult humans may contain high levels of antibody reactive with Candida albicans mannan. This study examined selected biological activities of such antibodies, focusing on sera that were collected from 34 donors and analyzed individually. The results showed that antimannan titers were normally distributed. Reactivity as determined by enzyme-linked immunosorbent assay with serotype A mannan generally paralleled reactivity with serotype B. Analysis of the kinetics for activation of the complement system and deposition of complement component 3 (C3) onto serotype A and serotype B cells showed a decrease in the lag time that occurred before the onset of rapid accumulation of C3 that correlated with increasing antimannan titers. In contrast, there was a decrease in the overall rate of accumulation of C3 on serotype A cells that was strongly correlated with increasing antibody titers; serotype B cells showed no such decrease. An evaluation of the contribution of mannan antibody to opsonophagocytic killing showed that mannan antibody in individual sera and antimannan immunoglobulin G (IgG) affinity purified from human plasma contributed to killing by neutrophils in a dose-dependent fashion in the absence of a functional complement system. However, affinity-purified antibody in very high concentrations was inhibitory to both complement-dependent and complement-independent opsonophagocytosis, and this finding suggests a prozone-like effect. In contrast, if the complement system was functional, antimannan IgG was not needed for opsonophagocytic killing. These results suggest that naturally occurring mannan antibodies and the complement system are functionally redundant for opsonophagocytic killing by neutrophils.


2017 ◽  
Vol 70 (12) ◽  
pp. 1074-1078 ◽  
Author(s):  
Alessandra Vecchione ◽  
Walter Florio ◽  
Francesco Celandroni ◽  
Simona Barnini ◽  
Antonella Lupetti ◽  
...  

AimsThe present study was undertaken to evaluate the discrimination ability of six chromogenic media in presumptive yeast identification.MethodsWe analysed 108 clinical isolates and reference strains belonging to eight different species: Candida albicans,Candida dubliniensis, Candida tropicalis, Candida krusei, Candida glabrata, Candida parapsilosis,Candida lusitaniae and Trichosporon mucoides.ResultsC. albicans, C. tropicalis and C. krusei could be distinguished from one another in all the tested chromogenic media, as predicted by the manufacturers. In addition, C. albicans could be distinguished from C. dubliniensis on BBL CHROMagar Candida, Kima CHROMagar Candida and Brilliance Candida, and C. parapsilosis could be identified on CHROMATIC Candida agar, CHROMOGENIC Candida agar, and Brilliance Candida agar.ConclusionsBrilliance Candida provided the widest discrimination ability, being able to discriminate five out of the seven Candida species tested. Interestingly, C. tropicalis and C. krusei could be already distinguished from each other after 24 hours of incubation.


2021 ◽  
Author(s):  
Alice Sperandio Porto ◽  
Elton Bill Amaral De Souza ◽  
Geyse Souza Santos ◽  
Anita Sperandio Porto ◽  
Judes Gonçalves Dos Santos

Introdução: Estudos na área nanobiotecnológica demonstraram que materiais, em diferentes escalas dimensionais, podem apresentar características físicas e químicas diferenciadas. As nanopartículas metálicas, sintetizadas de diferentes métodos, podem ser aplicadas em diferentes áreas como a medicina, veterinária, em especial, a área farmacêutica. As nanopartículas de prata (Ag-NPs) apresentam atividades antimicrobianas e podem ser obtidas por uma variedade de métodos químicos e físicos. Objetivos: O objetivo do presente estudo foi a obtenção de Ag-NPs pelo método da Reação de Combustão assistida via microondas e sua ação em cepas de três espécies de cândida, sendo elas: Cândida albicans, Cândida parapsilosis e Cândida tropicalis. Material e Métodos: Para a síntese de Ag-NPS foram utilizados como reagentes, o Nitrato de Prata (AgNO3) como agente oxidante a ureia ((NH₂)₂CO) como agente redutor em solução com água destilada. A composição da solução foi submetida a queima assistida em micro-ondas por aproximadamente 5 minutos. As Ag-NPs foram caracterizadas por Microscopia Eletrônica de Transmissão (MET) e Microscopia Eletrônica de Varredura (MEV) para estudos de morfologia e análise da dimensão do material obtido. Os ensaios para determinação da Concentração Inibitória Mínima (CIM), foram realizados utilizando a técnica de difusão em poços contidos nas placas com meio de cultura específico para leveduras, o ágar Sabouraud Dextrose. Foram utilizadas uma concentração de 20 µg/mL da solução de Ag-NPs adicionadas aos poços. Os ensaios da atividade antimicrobiana foram feitos em triplicata e comparado com o controle negativo (meio sem tratamento com Ag-NPs). Resultado: As microfotografias obtidas por MET e MEV constataram a obtenção de nanoestruturas com morfologia irregular, predominantemente, semi-esférica, e com dimensão variando entre 10 a 40 nanômetros. As Ag-NPs não apresentaram potencial antifúngico em relação as três espécies de Cândida estudadas, não sendo capazes de impedir o crescimento do fungo. Conclusão: Apesar de não apresentar efeito inibitório para as espécies de fungos escolhidas, novos ensaios devem ser realizados, utilizando diferentes técnicas de síntese de Ag-NPs e concentrações de agentes oxidantes e redutores diferentes, já que a associação de AgNO3 e (NH₂)₂CO como combustível, não apresentou eficácia quanto a inibição do halo de crescimento.


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