Identification of Trichosporon spp. Strains by Sequencing D1/D2 Region and Sub-typing by Sequencing Ribosomal Intergenic Spacer Region of Ribosomal DNA / 华中科技大学学报（医学）（英德文版）

To re-identify and further group 25 isolates of Trichosporon spp. identified morphologically previously, sequences of D1/D2 region of large subunit (LSU) of ribosomal DNA (rDNA) of 25 tested strains for identification and those of ribosomal intergenic space 1 (IGS1) region of 11 strains for sub-grouping were detected. The identifications of tested strains were changed except 6 strains. According to the alignment of the IGS1 region, 6 T. asahii isolates tested fell into 4 groups and 5 T. faecale isolates into 3 groups. Polymorphism of 2 T.japonicum isolates was found in 10 positions. With the alignments obtained in this research compared with the relative GenBank entries, it was found that T. asahii, T.faecale and T.japonicum species were divided into 7, 3 and 2 subtypes respectively. Morphological and biophysical methods are not sufficient for Trichosporon spp. identification. Sequencing becomes neces-sary for Trichosporon diagnosis. There is obvious diversity within a species.

Monitoring the effect of pyrene on the germination and radial growth of the wild and mutant strains of Rhizopus arrhizus UCP402

The physiological mutant of Rhizopus arrhizus was obtained in the pyrene resistance gradient test. Comparative studies were carried out about the behavior of the germination process and the radial growth of the mutant and wild strains of R. arrhizus UCP 402. Sabouraud Sucrose and Yeast Malt Broth cultures containing pyrene (10 mg/L) induced the germination process of the sporangiospores of the wild and mutant strains of R. arrhizus. The radial growth of the strains was inversely proportional to the pyrene concentration in the culture medium. The results showed an adaptation of R. arrhizus UCP 402x (mutant) in the pyrene (50mg/L) and suggested a higher ability of application in the removal of pyrene from the contaminated areas.

O mutante fisiológico de Rhizopus arrhizus foi obtido pelo teste do gradiente de resistência ao pireno. Estudos comparativos conduzidos sobre o comportamento do processo de germinação e o crescimento radial foram realizados entre as amostras selvagem e mutante de R. arrhizus UCP 402. Os meios Sabouraud Sacarose e Caldo de Levedura e Malte contendo pireno (10 mg/L) induziram ao processo de germinação de esporangiosporos das amostras selvagem e mutante de R. arrhizus. O crescimento radial das amostras foi inversamente proporcional à concentração de pireno no meio de cultura. Os resultados demonstraram uma excelente adaptação da amostra mutante de R. arrhizus UCP 402x na concentração de pireno (50 mg/L), sugerindo uma alta habilidade e possibilidade de aplicação na remoção de pireno em áreas contaminadas.

HIV-1 anti-retroviral drug effect on the C. albicans hyphal growth rate by a Bio-Cell Tracer system

Declining incidence of oropharyngeal candidosis and opportunistic infections over recent years can be attributed to the use of highly active anti-retroviral therapy (HAART). Infection with C. albicans generally involves adherence and colonization of superficial tissues. During this process, budding yeasts are able to transform to hyphae and penetrate into the deep tissue. Using the biocell tracer system, C. albicans hyphal growth was dynamically observed at the cellular level. Ritonavir was effective in the inhibition of hyphal growth with growth rate of 0.8 mum/min. This study showed the in vitro effect of HIV anti-retroviral drug on the growth rate of the C. albicans hyphae.

O declínio na incidência de candidose orofaríngea e infecções oportunistas associadas a infecção pelo HIV tem sido atribuído a introdução da terapia antiretroviral combinada (HAART). Infecção por C. albicans envolve aderência e colonização da mucosa superficial. Durante este processo leveduras são capazes de transformar-se na forma de hifas e penetrar nos tecidos mais profundos. Usando o sistema "Bio-Cell Tracer", o crescimento de hifas de C. albicans foi observado dinamicamente a nível celular. Ritonavir, inibidor de protease do HIV, foi efetivo na inibição do crescimento de hifas com media de 0.8 mim/min.O presente estudo demonstrou o efeito in vitro de um agente anti-retroviral HIV sobre o crescimento de hifas de C. albicans.

Candida dubliniensis in a Brazilian family with an HIV 1- infected child: identification, antifungal susceptibility, drug accumulation and sterol composition

This study investigated the prevalence of C. dubliniensis in a Brazilian family with an HIV - infected child. A total of 42 oral isolates were obtained from eight family members. The identification of C. dubliniensis was performed by polymerase chain reactions (PCR) using primers against a specific sequence of the C. dubliniensis cytochrome b gene. Only the HIV-infected child and his grandmother were colonized by C. dubliniensis. In this study C. dubliniensis isolated from the HIV-infected child exhibited high susceptibility for azoles tested with MICs of 0.125 and 0.5 æg/mL for voriconazole and fluconazole, respectively. Accumulation of [³H] fluconazole in C. dubliniensis isolated from the HIV-infected child was slightly reduced in comparison to the reference susceptible strain. C. dubliniensis isolates had significantly lower ergosterol levels in comparison to C. albicans reference strains.

O presente estudo investigou a prevalência de C. dubliniensis em uma família brasileira com uma criança infectada pelo vírus HIV. Um total de 42 isolados orais foram obtidos de 8 membros da família. A identificação de C. dubliniensis foi realizada por polymerase chain reactions (PCR) usando primers contra a sequência específica para o gene C. dubliniensis cytochrome b. Apenas a criança infectada pelo vírus HIV e a avó estavam colonizados por C. dubliniensis. Neste estudo C. dubliniensis isolado da criança infectada pelo vírus HIV exibiu alta susceptibilidade para azoles com concentração mínima inibitória de 0.125 and 0.5 æg/mL para voriconazole and fluconazole respectivamente. Acúmulo de [³H] fluconazol intra-celular foi ligeiramente reduzido em C. dubliniensis isolado da criança infectada pelo vírus HIV em comparação com a cepa referência sensível ao fluconazole. Isolados de C. dubliniensis neste estudo apresentaram níveis significantemente reduzidos de ergosterol da membrane celular em comparação com C. albicans.

Heavy metal biosorption by chitin and chitosan isolated from Cunninghamella elegans (IFM 46109)

Chitin and chitosan were extracted from mycelial biomass of Cunninghamella elegans and the performance for copper, lead and iron biosorption in aqueous solution was evaluated. The growth curve of C. elegans was accomplished by determination of biomass, pH, glucose and nitrogen consumption. Chitin and chitosan were extracted by alkali-acid treatment and the yields were 23.8 and 7.8 percent, respectively. For the adsorption analysis, the process of heavy uptake metal sorption was evaluated using polysaccharides solutions (1 percent w/v). The rate of metallic biosorption was dependent upon the concentration and pH of metal solutions, and the best results were observed with pH 4.0. Chitosan showed the highest affinity for copper and chitin for iron adsorption. The results suggest that C. elegans (IFM 46109) is an attractive source of production of chitin and chitosan, with a great potential of heavy metals bioremediation in polluted environments.

Effects of phosphorus on polyphosphate accumulation by Cunninghamella elegans

O crescimento, consumo de fosfato e glicose, bem como o conteúdo de fósforo, a distribuicão, estrutura e localizacão de polifosfato foram avaliados no micélio de Cunninghamella elegans cultivado em meios contendo diferentes concentracões de fosfato. Os resultados permitiram verificar a influência dessas concentracões de fosfato sobre o crescimento do fungo estudado. A maior concentracão de fosfato proporcionou maior rendimento da biomassa ao longo do crescimento. Uma relacão entre consumo de fosfato e glicose do meio foi observada em relacão ao crescimento e a quantidade de polifosfato total nos micélios cultivados nos diferentes meios de cultivo. Distintos métodos de extracão permitiram identificar e quantificar as diferentes fracões do polifosfato celular de Cunninghamella elegans. A citoquímica ultrastrutural foi utilizada com sucesso para identificar a localizacão e a distribuicão de polifosfato em Cunninghamella elegans. Os resultados revelaram diferencas no padrão de marcacão citoquímica nas diferentes fases do crescimento e meios de cultivo. Uma marcacão uniforme do polifosfato foi observada sobre a superfície celular, em especial, na parede celular e na membrana citoplasmática. Produtos de reacão resultantes da marcacão citoquímica foram também visualizados em estruturas trabeculares, vacuolares, vesiculares, sob a forma de corpos eletrondensos e grânulos dispersos no citoplasma. Os resultados demonstraram o potencial de Cunninghamella elegans na acumulacão de polifosfato, sugerindo uma possível aplicacão em processos biotecnológicos.

A DNA Genotyping Study of Candida Isolates from Mothers and Their Neonates / 中华皮肤科杂志

Objectives To identify the route and time of transmission by Candida species from mothers' vagina to their neonates' mouth.Methods Specimens for fungal cultures were obtained from vaginal discharge of mothers just before delivery and also from the mouth of their offspring just after birth.Eleven mother-infant pairs were investigated.Candida species was identified based on morphology,biochemical analysis,and sequencing of D1/D2 domain of the large subunit of ribosomal DNA (LSUrDNA).Electrophoretic karyotyping (EK) and random amplified polymorphic DNA analysis (RAPD) were performed to search for DNA homology.Results Candida isolates (16 strains) from 8 mother-infant pairs were identified as Candida albicans by 100% homology of their D1/D2 sequences with reference strain C.albicans Y-12983 (GenBank access No.U45776).Similarly,4 strains from two mother-infant pairs and 2 isolates from the other pair were identified as Candida glabrata and Candida krusei,respectively,by 100% homology in sequences alignment of the domains with reference strains,C.glabrata Y-65(U44808) and C.krusei Y-5396 (U76347).The same EK profiles were found for each C.albicans or C.krusei strain pair from both mother and her neonate.Although different EK bands with various molecular size were generated for each C.glabrata isolate pair,they were still considered to be homologous based on the fact that main EK bands were identical.Each isolate pair from mother and her infant presented almost the same RAPD profile,except for one pair,isolates F7n and F7m,which showed minor diverse DNA bands.Conclusion Eleven Candida isolates from neonates have identical molecular characteristics with their mother's isolates.Vertical transmission may be the main pathway of Candida spp.from mothers to their neonates.

Characterization of Pseudallescheria boydii and Scedosporium apiospermum by Random Amplification of Polymorphic DNA Assay / 中华皮肤科杂志

Objective To investigate the DNA polymorphism of Pseudallescheria boydii and Scedosporium apiospermum and to analyze the relationship between random amplification of polymorphic DNA (RAPD) patterns and geographic origins.Methods The genomic DNAs of 13 Pseudallescheria boydii strains and 18 Scedosporium apiospermum strains isolated from 5 countries were amplified with RAPD technique.Results All strains tested were classified into 31 patterns by combination of the results obtained with 3 primers.The cluster tendency was identified based on species difference,namely,P.boydii or S.apiospermum strains,however,no such cluster tendency was revealed based on geographic origins of the most of strains,by dendrogram analysis.Conclusions The infraspecific variability of P.boydii and S.apiospermum is considerable.The cluster tendency of RAPD profiles is of consistency with morphological properties of P.boydii and S.apiospermum to some degree,however,is of no correlation with geographic origins of the pathogenic strains.

Faster Chitosan productions by mucoralean strains in submerged culture

Production of chitosan was conducted using two Mucoralean strains, Mucor racemosus and Cunninghamella elegans. Chitosan was extracted from mycelia of M. racemosus and C. elegans at different growth phases on YPD medium. In both fungi, chitosan was rapidly produced, while highest yield of extractable chitosan was found in 24h of cultivation in submerged culture. The yield of chitosan isolated from dry mycelia of M. racemosus was about 40 per cente higher than from C. elegans. The degree of N-acetylation of chitosan was 49 per cente in M. racemosus and 20 per cente in C. elegans, and the D-glucosamine contents were about 48 per cente and 90 per cente, respectively.

Extraction and characterization of proteins from cell walls of two strains of paracoccidioides brasiliensis

En el presente trabajo se analizaron las proteínas de la pared celular de 2 cepas de paracoccidioides brasiliensis en fase levaduriforme (PbHC-PE y Pb 18). Las proteínas fueron extraidas por tres difrentes métodos y estudiadas por electroféresis SDS-PAGE. Los resultados de los perfiles de las dos cepas fueron diferentes, permitiendo la posibilidad de su uso como marcadores quimiotaxonómicos. Se observó una secreción transitoria de la proteína gp 43 a través de la pared celular de las cepas de p. brasiliensis.