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1.
High activities of extracellular pectinase with viscosity-diminishing and reducing groups-releasing activities were produced by Penicillium frequentans after 48 h at 35°C, in agitated cultures supplemented with 0.5% citrus pectin and initial pH of 2.5. Under these conditions the fungus also produced high activity of pectinesterase. At an initial pH of 7.0 or 8.0, pectin lyase activity was also detected. Enzyme activity releasing reducing sugars was more stable at 50°C than viscosity-diminishing activity. Both activities were maximal at pH 2.5 to 5.2 and at 55°C.The authors are from the Faculdade de Ciências Farmacêuticas de Ribeirão Preto da Universidade de São Paulo, Avenida do Café, s/no, Bairro Monte Alegre, 14.049 Ribeirão Preto, S.P., Brazil.  相似文献   

2.
The partially-purified, thermally-stable trehalase from conidia of Humicola grisea was highly specific for trehalose and was free of potentially interfering activities. The enzyme was fully stable when stored in solution at -15°C for at least 6 months. This preparation could be used to quantify trehalose from 0.05 to 1.25 mol/ml either in carbohydrate mixtures or in complex biological materials.M.J. Neves, H.F. Terenzi and J.A. Jorge are with Departmento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirao Preto, Universidade de São Paulo, 14040-901-Ribeirão Preto, São Paulo, Brazil; F.A. Leone is with Departamento de Quimica, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901-Ribeirão Preto, São Paulo, Brazil.  相似文献   

3.
H. grisea produced an extracellular -glucosidase (EC 3.2.1.21) at high activity in media supplemented with carboxymethyl cellulose (CMC) or cellobiose. Cellobiose-induced -glucosidase was insensitive to glucose repression whereas that of CMC-supplemented cultures was partially repressed. Molecular sieving revealed three main active components (Mr 50, 128 and 240 kDa). Glucose competitively inhibited -glucosidase activities with Ki values of 0.9mM and 3.3mM (extracellular) and 10.2mM and 22.6mM (cytosolic), induced in the presence of CMC or cellobiose respectively.The authors are with the Departamento de Biologia, Faculdade de Filosofia. Ciências e Letras de Ribeirão Preto, Universidade de São Paulo-14040-901 Ribeirão Preto, São Paulo, Brasil;  相似文献   

4.
A mutation of the ctsA locus of Aspergillus nidulans affects both the radial growth and conidiation of the mould when grown in the presence of citrate. The ctsA locus was allocated to linkage group IV but it recombines freely with inoB2 and pyroA4 (which are also in linkage group IV). It is recessive in heterozygous diploids. A possible role for this gene in maintaining membrane integrity is discussed.The authors are with the Departamento de Genética, FMRP-USP, Av. Bandeirantes, 3900, 14049 Ribeirão Preto, SP., Brazil.  相似文献   

5.
The authors report the first six cases of disseminated histoplasmosis and acquired immunodeficiency syndrome (AIDS) seen at the University Hospital, Faculty of Medicine of Ribeirão Preto, University of São Paulo, from 1987 to 1989, with emphasis on dermatological clinical manifestations, nasal mucosa lesions and treatment. The mycosis was the first manifestation of AIDS in four patients. It is concluded that biopsies of the lesions for histopathologic study and fungal culture are important for diagnosis.  相似文献   

6.
Summary Observations on the nesting activities ofMicrothurge corumbae, carried out at the University Campus of Ribeirão Preto, São Paulo, Brazil, from 1977 to 1981, indicated that 61.9 % of nests were re-used by succeeding generations. Re-use by one generation was more frequent than by two generations, and re-use by a third was observed only once. Nests were re-used by one or several females. Single females were more frequently in the first re-use. In these cases nest re-use did not differ essentially from the solitary foundation of a new nest, except for the adoption of a pre-existing nest without excavation. In multifemale nests, analysis of relative age (wing wear), ovarian and spermathecal conditions of associated females and the content of nests at excavation indicated that the social pattern in such colonies is communal. There is some evidence that the associated females are relatives. The chalcidoid waspLeucospis was the principal nest parasite, and ants of the genusCrematogaster were nest predators. In multifemale nests, the rate of parasitism was significantly lower than in solitary nests, indicating that nest-sharing resulted in improved nest defense. On the other hand, the absence of predation on immatures of the first generation of M.commbae in multifemale nests suggests that such nests are also more resistant to attack by predators.  相似文献   

7.
Tyrosinase derepression in Neurospora mycelia grown in Vogel medium, submitted to starvation in phosphate buffer 0.1 M, pH 6.0, was abolished by exogenous magnesium sulfate. This effect seemed to be caused by the sulfate ion itself and not by a sulfate-derivative. Sulfate repression required protein synthesis, thus suggesting the involvement of a specific gene product mediating sulfate repression. Cultures made in Westergaard and Mitchell crossing medium became competent for sexual development and could be stimulated to form tyrosinase either by mating or starvation. In that case the enzyme derepression was insensitive to the sulfate effect. The possible existence of a positive mechanism for the control of tyrosinase activity during sexual development is suggested.This work is a part of two theses, by Rolf Alexander Prade and Angela Kaysel Cruz submitted to the Departments of Biochemistry and Physiology, respectively, of the School of Medicine of Ribeirão Preto in partial fulfillments of the requirements for the Master Degree.  相似文献   

8.
Strains Paenibacillus sp. BP-23 and Bacillus sp. BP-7, previously isolated from soil from a rice field, secreted high levels of pectinase activity in media supplemented with pectin. Production of pectinases in strain Paenibacillus sp. BP-23 showed catabolite repression, while in Bacillus sp. BP-7 production of pectin degrading enzymes was not negatively affected by glucose. The two strains showed lyase activities as the predominant pectinases, while hydrolase activity was very low. Analysis of Paenibacillus sp. BP-23 in SDS–polyacrylamide gels and zymograms showed five pectinase activity bands. The strict requirement of Ca2+ for lyase activity of the strain indicates that correspond to pectate lyases. For Bacillus sp. BP-7, zymograms showed four bands of different size. The strain showed a Ca2+ requirement for lyase activity on pectate but not on pectin, indicating that the pectinolytic system of Bacillus sp. BP-7 is comprised of pectate lyases and pectin lyases. The results show differences in pectin degrading systems between the two aerobic sporogenous bacterial strains studied.  相似文献   

9.
A polymorphic system of ADH isozymes is described in the honeybee Apis mellifera. Three and six different electrophoretic patterns were found, respectively, in drone and worker pupae analysis. The data indicate that the ADH isozymes are controlled by three alleles, Adh-1 1, Adh-12, and Adh-1 3. The frequency of the Adh-1 alleles is different in two analyzed subspecies, Apis mellifera adansonii (African bees) and Apis mellifera ligustica (Italian bees). In the African bees, the frequencies are 0.256 and 0.697 for Adh-1 1 and Adh-12, respectively. In the Italian bees, these values are shown to be 0.902 and 0.098, respectively. The allele Adh-1 3 was not detected in the Italian bee population. The effect of NAD on the resolution of this system was investigated, and only one region of ADH activity was obtained in drone pupae analysis when NAD was used in the gels. However, two different regions of activity were observed in the same samples, in the absence of the coenzyme. ADH activity was not detected in young larvae, but it increased to a maximum in prepupal and white-eyed pupal phases. It then declined progressively to total absence in the emerging bees.This work was supported by the Brazilian Research Council (CNPq) and S~ao Paulo State Research Foundation (FAPESP). This study was performed by the senior author in partial fulfillment of the requirements for a master's degree and was directed by Dr. M. A. Mestriner, Genetics Department, University of São Paulo at Ribeirão Preto.  相似文献   

10.
Using anion-exchange chromatography on different carriers and phenyl-Sepharose hydrophobic chromatography, five pectolytic enzymes were isolated from the culture liquid of a mutant strain of Aspergillus japonicus: two endo-polygalacturonases (I and II, 38 and 65 kD, pI5.6 and 3.3), pectin lyase (50 kD, pI3.8), and two pectinesterases (I and II) with similar molecular weights (46 and 47 kD) and the same pI(3.8). The pectinesterases apparently represent two isoforms of the same enzyme. All purified enzymes were homogenous according to SDS-PAGE and polyacrylamide gel-IEF, except for endo-polygalacturonase II that gave two bands on isoelectric focusing, but one band on electrophoresis. All enzymes had maximal activity in an acid medium (at pH 4.0-5.5). The pectin lyase and pectinesterase were stable at 40-50°C. The thermal stability of both endo-polygalacturonases was much lower (after 3 h of incubation at 30°C, endo-polygalacturonases I and II lost 40 and 10% of the activity, respectively). The activity of endo-polygalacturonases I and II towards polygalacturonic acid strongly depended on NaCl concentration (optimal concentration of the salt was 0.1-0.2 M); the enzymes were also capable of reducing the viscosity of pectin solution, but rather slowly. The pectin lyase had no activity towards polygalacturonic acid. The activity of the pectin lyase increased with increasing degree of methylation of pectins. Both endo-polygalacturonases demonstrated synergism with the pectinesterase during the hydrolysis of highly methylated pectin. On the contrary, in the mixture of pectin lyase and pectinesterase an antagonism between the two enzymes was observed.  相似文献   

11.
Summary The authors review and comment on Brazilian literature on the observations of South American Blastomycotic lesion in perineal, anal and/or rectal localization.They relate a case of a patient presenting a perineal lesion two years after the excision of a tumor caused byP. brasiliensis in the brain.They comment onMackinnon's pathogenic theory of South American Blastomycosis that presumes that lungs are the portal of entry ofP. brasiliensis by inhalation of its spores. Thus, mucocutaneous lesions are secondary to a primary pulmonary localization by hematogenous route.
Sumário Os autores revisam e comentam a literatura brasileira sôbre as observacões de Blastomicose Sul-americana com localização peineoano-retal.Relatam a observação de um paciente no qual a lesão perineal surgiu dois anos após a ablação de um tumor do cérebro porP. brasiliensis.Discutem a casuística à luz da teoria patogênica deMackinnon, admitindo que a porta de entrada do fungo seja pelas vias aéreas, por inhalação dos espórios do fungo. As lesões mucocutãneas são pois secundárias à localização pulmonar primária, (às vêzes inaparantes) da qual resultam por disseminaçåo hematógena.
  相似文献   

12.
A case of paracoccidioidomycosis with ocular involvement is studied. Brazilian literature is reviewed. The scarcity of human ocular mycosis is commented on. The most frequent clinic aspects of ocular lesions in natural mycosis are described.
Resumo Um caso de paracoccidioidomicose pulmonar e linfática seguido de comprometimento conjuntivo-palpebral é estudado, em São Paulo.A literatura nacional é revista. As lesões oculares, mais frequentemente verificadas, na paracoccidioidomicose natural são descritas, minuciosamente. O pequeno número de casos humanos com comprometimento ocular é discutido.A severidade e a frequencia das lesões oculares em animais inoculados intracardiacamente, com cultivos de P. brasiliensis sugerem disseminação hematogênica ocular da paracoccidioidomicose humana.
  相似文献   

13.
A freshly-prepared yeast extract at 30 or 50 g/l improved the growth of Bradyrhizobium japonicum SEMIA 587 in a 5-l stirred fermenter. Monosodium glutamate or a commercial yeast extract at 2.0 g/l almost doubled cell mass productivity and cell viability when added at the end of the first exponential growth phase.The authors are with the Divisão de Quimica, Agrupamento de Biotecnologia, Instituto de Pesquisas Tecnológicas do Estado de São Paulo, S/A.-IPT-Cidade Universitária s/n., Caixa Postal 7141, CEP 01064-970, São Paulo, SP, Brazil  相似文献   

14.
The decrease in viscosity is widely used to estimate the activity of pectinolytic enzymes. This method is shown to be influenced by the production strain and this prevents an accurate comparison between the activities of different microorganisms, especially under different conditions.A.E. Maiorano and Y. Ogaki are with the Divisão de Quimica, with the Agrupamento de Biotecnologia, Instituto de Pesquisas Tecnológicas do Estado de São Paulo S/A.-IPT, Cidade Universitária, Caixa Postal 7141, CEP 01064-970, São Paulo, SP, Brazil; W. Schmidell is with the Departamento de Engenharia Quimica, Escola Politécnia, Universidade de São Paulo, Caixa Postal 61548, CEP 05424-970, São Paulo, SP, Brazil.  相似文献   

15.
Seven different strains were selected for their ability to degrade citrus pectin. Alkaline pectinases were produced by five bacterial soil isolates, whereas two fungal strains produced pectinase in an acidic environment. The bacteria were isolated from soil of a plum orchard in Northern Ireland. These isolates produced significant amounts of pectin lyase (PL) and polygalacturonase (PG) with maximum activities of 30.1 and 29.1 U/ml respectively. Fungal strains Aspergillus sp. and PN-1 produced four different pectinolytic activities; endo-PG, exo-PG, pectin esterase (PE) and PL. The Aspergillus sp. produced higher amounts of pectinase than PN-1. The Aspergillus sp. excreted highly stable pectinases, which may be of importance for industrial applications.  相似文献   

16.
Pectinase production by Tubercularia vulgaris using orange-pulp pellets (OPP) or citrus pectin as carbohydrate sources was investigated. The highest levels of extracellular polygalacturonase were detected with OPP as inducing substrate. The pectinases present in the crude filtrate from T. vulgaris cultures included methyl esterase, endo-polygalacturonase and exo-polygalacturonase activities with both substrates. Moreover, in medium supplemented with OPP, the additional presence of one endo-polygalacturonase and two exo-polygalacturonases was detected.  相似文献   

17.
Feeding experiments with two species of carnivorous copepod, Mesocyclops longisetus (Thiebaud) and Mesocyclops kieferi Van de Velde from Barra Bonita, a eutrophic reservoir in São Paulo, Brasil, were performed using two common types of prey: Ceriodaphnia cornuta, a cladoceran, with a mean body length of 464 µm (including spines) or 393 µm (without spines), and Brachionus calyciflorus, a rotifer with a mean body length of 350 µm (including spines) or 279 µm (without spines).Both species showed higher consumption rates on Brachionus than on Ceriodaphnia. For Mesocyclops longisetus, the average rates were: 2.19 prey ind–1 h–1 (Brachionus), and 1.30 prey ind–1 h–1 (Ceriodaphnia). For Mesocyclops kieferi, the rates were 1.85 prey ind–1 h–1 (Brachionus) and 0.60 prey ind–1 h–1 (Ceriodaphnia). These experimental data are discussed with reference to the dynamics of the predator and prey populations in the reservoir.Laboratorio de Limnologia, Departamento de Ciencias Biologicas, Universidade Federal de São CarlosCentro de Recursos Hidricos e Ecologia Aplicada Lab. de Limnologia, Departamento de Hidraulica e Saneamento, Escola de Engenharia de São Carlos, Universidade de São Paulo  相似文献   

18.
We examined the relationship between food patch size and feeding party size with comparative data from two populations of muriquis (Brachyteles arachnoides) in the 37,797-ha forest at the Parque Estadual de Carlos Botelho (PECB), São Paulo, and the 800-ha forest at the Estação Biológica de Caratinga (EBC), Minas Gerais. Precipitation was more abundant and less seasonal at PECB than EBC, and the density of large trees (>25.0 cm) was higher at PECB (206 ha –1 ) than at EBC (132 ha –1 ). At both sites, the size of feeding parties is positively related to the size of food patches. As predicted, food patches at PECB are significantly larger than those at EBC for both fruit and leaf sources. Contrary to expectations, feeding parties were larger at EBC than PECB. The higher population density of muriquis and sympatric primates at EBC may make large associations more advantageous to these muriquis than to muriquis living at lower population densities in PECB.  相似文献   

19.
Summary Elytrosporangium (Greek Elytron, pod), a new genus of Actinomycetales from soil, placed in the family ActinoplanaceaeCouch, and its type species,E. brasiliense, are described. The main characteristic of the new genus is the production, in the substratal mycelium, of pod-shaped sporangia (merosporangia) with non-motile, globose, subglobose, to more or less cylindrical sporangiospores in chains. In addition, aerial mycelium with spores in chains, as inStreptomyces, is produced.
Zusammenfassung Elytrosporangium (griechisch: Elytron, Schote) eine neue Gattung von Actinomycetels des Bodens wird hier zusammen mit der ArttypeE. brasiliense beschrieben. Das Hauptmerkmal der genannten Gattung ist die Erzeugung von Sporangien in Schotenform (Merosporangien) im vegetativen Myzel. Die Sporangien bilden sich sowohl am Ende von Haupthyphen als auch in kleinen seitlichen Zweigen, einzeln oder als Trauben, von zwei bis fünf. Die Sporangiosporen bilden eine Kette, die Basale mehr oder weniger zylindrisch und die übrigen fast kugelförmig. Luftmyzel mit Ketten von Konidien können erzeugt werden wie inStreptomyces. Wir betrachten die beschriebene Gattung als zur Familie Actinoplanaceae gehörend.Die Arttype wurde isoliert von Bodenproben welche gesammelt wurden in einen Bodenprofil von 45 cm Tiefe in Verfolg des Programms einer Mikrobiologischen Prospektion des Bodens im Nordosten von Brasilien welches IMUR gemeinsam mit anderen brasilianischen wissenschaftlichen Körperschaften ausführt.

Sumário Elytrosporangium (grego Elytron, vágem), um novo gênero de Actinomycetales do solo é descrito, juntamente com sua espécie tipo,E. brasiliense, A principal característica do gênero em foco é a produção de esporângios em forma de vágem (merosporângios), no micélio vegetativo. Os esporângios formam-se tanto na extremidade de hifas principais como na de pequenos ramos laterais, isoladamente ou em cachos de dois a cinco.Os esporangiosporos constituem uma cadeia, os basais sendo mais ou menos cilíndricos e os demais globosos ou subglobosos.Um micélio aéreo exibindo cadeias de conídios pode ser produzido, como emStreptomyces.Consideramos o gênero em causa como integrante da familia Actinoplanaceae. A espécie tipo foi isolada de amostra de solo coletada num perfil, a 45 cm de profundidade, como decorrência de programa de prospecção microbiológica dos solos do Nordeste do Brasil que o IMUR vem desenvolvendo em colaboração com entidades científicas brasileiras.


IMUR, Publ. no. 467.  相似文献   

20.
Summary. The nesting behavior of the euglossine bee Euglossa townsendi was studied on the campus of the University of São Paulo-Ribeirão Preto, SP, Brazil, from January 1994 to December 1999, using artificial nesting substrate and observation boxes. Twenty-one nests were founded during the study period, with the highest frequencies of nesting occurring during the hot, wet season. Each nest was founded by a single female and, after the completion of the last cell, she spent most of her time in the nest. The males left the nest immediately after emergence and did not return. Some females left the nest within a few days of eclosing, while others stayed in their natal nests and began to reactivate them. Reactivations were performed by a single female, by one or more females in the presence of the mother, by more than one female in the absence of the mother, and by more than one female in the presence of females that participated in the prior reactivation. According to behavior, the females were classified as forager/egg-laying and egg-laying females. The oviposition by egg-laying females was always preceded by oophagy. All of the forager/egg-laying and egg-laying females that were dissected had been inseminated. The behavior displayed by egg-laying females is characteristic of brood parasitism and fits the parental parasitism hypothesis developed as an alternative pathway by which insect sociality could have arisen. The behaviors displayed by E. townsendi, together with those reported for Euglossa cordata, show that both species have bionomic traits that resemble the conditions suggested as precursors of the origin of eusociality.Received 12 June 2003; revised 6 April 2004; accepted 22 April 2004.  相似文献   

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