Production of proline and protease with different organic wastes in bacteria (Production proline and protease with organic wastes) / Produção de prolina e protease com diferentes resíduos orgânicos em bactérias (produção de prolina e protease com resíduos orgânicos)

In this study, we investigated the proline and protease production of different bacteria in several organic waste materials. Our aim was to produce proline and protease economically in waste that is abundantly available while reducing its environmental impact. 5 ml of different organic waste materials (OWW: Olive waste water; N.B: Nutrient Broth; EW: Eggshell; PBS: PBS buffer; PLW: Peach leaf wastes; TCW: Turkish coffee wastes; TWW: Tea waste water; WCW: Waste cheese whey; WFO: Waste frying oil) were placed in 10 ml grow tubes, inoculated and incubated for 24 h. Phosphate-buffered saline and 10% solutions of different organic wastes were added. These cultures were subsequently incubated at 37°C for 24 h. Cells were harvested at 24 h for L-proline assay. 1 ml of culture was transferred by pipette into an Eppendorf tube and centrifuged at 14,000 rpm for 20 min at room temperature. Cellular debris was removed by centrifuge and the supernatant was used for proline activity assays. Protease activity was determined using a modified method with casein as the substrate. We found that proline and protease can easily be produced economically using Turkish coffee wastes (TCW), Waste cheese whey (WCW) and Olive waste water (OWW) organic waste. We believe that this study will result in similar research leading to the economical use of these waste materials thus reducing their impact on the environment.

Neste estudo, investigamos a produção de prolina e protease de diferentes bactérias em diversos resíduos orgânicos. Nosso objetivo era produzir prolina e protease economicamente em resíduos que estão disponíveis em abundância, reduzindo seu impacto ambiental. Cinco ml de diferentes materiais de resíduos orgânicos (OWW: resíduos de azeitona; NB: caldo nutriente; EW: casca de ovo; PBS: tampão PBS; PLW: resíduos de folhas de pêssego; TCW: resíduos de café turco; TWW: resíduos de chá; WCW: resíduos de queijo soro de leite; WFO: óleo de fritura residual) foram colocados em tubos de cultivo de 10 ml, inoculados e incubados por 24 horas. Adicionaram-se solução salina tamponada com fosfato e soluções a 10% de diferentes resíduos orgânicos. Essas culturas foram subsequentemente incubadas a 37° C durante 24 h. As células foram colhidas às 24 h para o ensaio de L-prolina. Um ml de cultura foi transferido por pipeta para um tubo Eppendorf e centrifugado a 14.000 rpm, por 20 min, em temperatura ambiente. Os detritos celulares foram removidos por centrifugação e o sobrenadante foi usado para ensaios de atividade de prolina. A atividade da protease foi determinada usando um método modificado com caseína como substrato. Descobrimos que a prolina e a protease podem ser facilmente produzidas economicamente, usando resíduos de café turco (TCW), resíduos de soro de queijo (WCW) e resíduos orgânicos de água de oliva (OWW). Acreditamos que este estudo resultará em pesquisas semelhantes, levando ao uso econômico desses materiais residuais, reduzindo, assim, seu impacto no meio ambiente.

Amino Acid Supplementation Improves the Production of Extracellular Peptidases by Aspergillus Section Flavi and their Ionic Immobilization

Abstract Bioprocess studies have been highlighted due to the importance of physiological processes and industrial applications of enzymes. The potential of peptidase production from Aspergillus section Flavi using different amino acids as a supplemental nitrogen source was investigated. A production profile revealed that amino acids had positive effects on peptidase production when compared to the control without amino acids. Optimal production (100 U/mL) was obtained with Arginine amino acid in 96 h of fermentation. Extracellular peptidase from Aspergillus section Flavi was identified in submerged bioprocesses by in situ activity. Biochemical studies revealed that the maximum activities of the enzyme extract were obtained at pH 6.5 and a temperature of 55°C. The inhibition by EDTA and PMSF suggests the presence of more than one peptidase while the Ni2+ and Cu2+ had a negative influence on the enzyme activity. When the crude extract was reversibly immobilized on ionic supports, DEAE-Agarose and MANAE-Agarose the derivative showed different profiles of thermal and pH stabilities. Hence, this study revealed the basic properties and biochemical characteristics that allowed the production improvement of this class of enzyme. Moreover, with known properties stabilization and immobilization process is required to further explore its biotechnological capacities.

In vitro evaluation of hydrolytic enzyme activity and biofilm formation of Candida parapsilosis species complex from a nosocomial environment

Abstract INTRODUCTION: Candida parapsilosis complex species, frequently found in hospital environments, have gained importance as etiological agents of candidemia. METHODS: Candida parapsilosis complex isolates from a nosocomial environment were identified and their hydrolitic enzyme activity and ability to form biofilm were characterized. RESULTS: Twenty-two C. parapsilosis sensu stricto isolates produced proteinase and three produced phospholipase. Most Candida metapsilosis isolates produced proteinase and one also produced phospholipase. All 29 isolates formed biofilms. CONCLUSIONS: The nosocomial environment may act as a reservoir for C. parapsilosis complex isolates with phenotypic features that could possibly lead to nosocomial infections and health complications in hospital patients.

Simultaneous production of amylases and proteases by Bacillus subtilis in brewery wastes

ABSTRACT The simultaneous production of amylase (AA) and protease (PA) activity by Bacillus subtilis UO-01 in brewery wastes was studied by combining the response surface methodology with the kinetic study of the process. The optimum conditions (T = 36.0 °C and pH = 6.8) for high biomass production (0.92 g/L) were similar to the conditions (T = 36.8 °C and pH = 6.6) for high AA synthesis (9.26 EU/mL). However, the maximum PA level (9.77 EU/mL) was obtained at pH 7.1 and 37.8 °C. Under these conditions, a considerably high reduction (between 69.9 and 77.8%) of the initial chemical oxygen demand of the waste was achieved. In verification experiments under the optimized conditions for production of each enzyme, the AA and PA obtained after 15 h of incubation were, respectively, 9.35 and 9.87 EU/mL. By using the Luedeking and Piret model, both enzymes were classified as growth-associated metabolites. Protease production delay seemed to be related to the consumption of non-protein and protein nitrogen. These results indicate that the brewery waste could be successfully used for a high scale production of amylases and proteases at a low cost.

Enhanced production and organic solvent stability of a protease fromBrevibacillus laterosporus strain PAP04

A bacterial strain (PAP04) isolated from cattle farm soil was shown to produce an extracellular, solvent-stable protease. Sequence analysis using 16S rRNA showed that this strain was highly homologous (99%) to Brevibacillus laterosporus. Growth conditions that optimize protease production in this strain were determined as maltose (carbon source), skim milk (nitrogen source), pH 7.0, 40°C temperature, and 48 h incubation. Overall, conditions were optimized to yield a 5.91-fold higher production of protease compared to standard conditions. Furthermore, the stability of the enzyme in organic solvents was assessed by incubation for 2 weeks in solutions containing 50% concentration of various organic solvents. The enzyme retained activity in all tested solvents except ethanol; however, the protease activity was stimulated in benzene (74%) followed by acetone (63%) and chloroform (54.8%). In addition, the plate assay and zymography results also confirmed the stability of the PAP04 protease in various organic solvents. The organic solvent stability of this protease at high (50%) concentrations of solvents makes it an alternative catalyst for peptide synthesis in non-aqueous media.

Fibrinolytic protease production by new Streptomyces sp: DPUA 1576 from Amazon lichens

Background Streptomyces sp. DPUA 1576 from Amazon lichens was studied to protease and fibrinolytic production. A 2² factorial experimental design was applied to optimize its protease enzyme production using two independent variables, namely soybean flour and glucose concentrations. Results The optimal conditions to obtain high protease production (83.42 U/mL) were 1.26% soybean flour and 1.23% glucose concentration. A polynomial model was fitted to correlate the relationship between the two variables and protease activity. In relation to fibrinolytic activity, the highest activity of 706.5 mm² was obtained at 1.7% soybean flour and 1.0% glucose concentration, which was 33% higher than plasmin. Fibrinolytic production was not optimized in the studied conditions. Conclusions These results show that the optimization of the culture medium can enhance protease production, thus becoming a good process for further research. In addition, Streptomyces sp. DPUA 1576, isolated from Amazon lichens, might be a potential strain for fibrinolytic protease production.

Manual and Rotary Instrumentation Ability to Reduce Enterococcus faecalis Associated with Photodynamic Therapy in Deciduous Molars

This aim of this study was to assess the ability of manual or rotary instrumentation associated with photodynamic therapy (PDT) to reduce Enterococcus faecalis using three combinations of light/photosensitizers: toluidine blue O/laser, fuchsin/halogen light and fuchsin/LED. Twenty deciduous molars were selected and contaminated with Enterococcus faecalis (McFarland 0.5 scale). Working length determination was performed by visual method. The teeth were randomly divided into two groups: G1 (n=10): manual instrumentation (Kerr-type files) and G2 (n=10): rotary instrumentation (ProTaper system). The bacteria were collected three times using sterile paper cones compatible with the anatomic diameter of the root canal for 30 s before and after instrumentation and after PDT. The samples were diluted in peptone water, seeded on blood agar plates and incubated in an oven at 37 °C for colony-forming units counting. The decrease of E. faecalis counts after instrumentation and after PDT was compared using the Wilcoxon test, t-test and Kruskal Wallis test. A significant reduction of E. faecalis occurred after manual and rotary instrumentation and after PDT using the three combinations of light/photosensitizer (p<0.05). It may be concluded that both rotary and manual instrumentation reduced E. faecalis. Fuchsin with halogen light or LED irradiation and toluidine blue O with laser irradiation can be used to reduce E. faecalis in root canals of primary molars. PDT can be used as an adjuvant to conventional endodontic treatment.

O objetivo do presente estudo foi avaliar a redução de Enterococcus faecalis após instrumentação manual ou rotatória associada à terapia fotodinâmica (PDT) utilizando 3 combinações luz/fotossensibilizante: azul de toluidina O/laser, fucsina/luz halógena e fucsina/LED. Foram selecionados 20 molares decíduos que foram contaminados com Enterococcus faecalis (escala 0,5 de McFarland). A odontometria foi feita através do método visual. Os dentes foram divididos aleatoriamente em dois grupos: G1 (n=10): instrumentação manual (limas tipo Kerr) e G2 (n=10): instrumentação rotatória (sistema ProTaper). Foram realizadas coletas com cone de papel estéril compatível com o diâmetro anatômico do canal durante 30 s antes e após a instrumentação e a PDT. As amostras foram diluídas em água peptonada, semeadas em placas de agar-sangue e incubadas em estufa a 37 °C para contagem das unidades formadoras de colônias. As comparações antes da redução de E. faecalis após a instrumentação e após a realização da PDT foram realizadas pelo teste de Wilcoxon, teste t e Kruskal Wallis. Houve redução significante de E. faecalis após a instrumentação manual ou rotatória e após realização da PDT com as três combinações de luz/fotossensibilizante (p<0,05). Pode-se concluir que a instrumentação rotatória e manual acarretou a redução de E. faecalis. A fucsina irradiada com luz halógena ou led e o azul de toluidina irradiado com laser podem ser utilizados para redução de E. faecalis do sistema de canais radiculares de molares decíduos. A terapia fotodinâmica pode ser utilizada como coadjuvante ao tratamento endodôntico convencional.

Determination of germ tube, phospholipase, and proteinase production by bloodstream isolates of Candida albicans

Introduction Candida albicans is a commensal and opportunistic agent that causes infection in immunocompromised individuals. Several attributes contribute to the virulence and pathogenicity of this yeast, including the production of germ tubes (GTs) and extracellular hydrolytic enzymes, particularly phospholipase and proteinase. This study aimed to investigate GT production and phospholipase and proteinase activities in bloodstream isolates of C. albicans. Methods One hundred fifty-three C. albicans isolates were obtained from blood samples and analyzed for GT, phospholipase, and proteinase production. The assays were performed in duplicate in egg yolk medium containing bovine serum albumin and human serum. Results Detectable amounts of proteinase were produced by 97% of the isolates, and 78% of the isolates produced phospholipase. GTs were produced by 95% of the isolates. A majority of the isolates exhibited low levels of phospholipase production and high levels of proteinase production. Conclusions Bloodstream isolates of C. albicans produce virulence factors such as GT and hydrolytic enzymes that enable them to cause infection under favorable conditions. .

Optimization of protease production by the fungus Monacrosporium thaumasium and its action against Angiostrongylus vasorum larvae / Otimização da produção de protease pelo fungo Monacrosporium thaumasium e sua ação contra larvas de Angiostrongylus vasorum

The objectives of this study were to optimize protease production from the nematophagous fungus Monacrosporium thaumasium (NF34a) and evaluate its larvicidal activity and biological stability. An isolate of the nematophagous fungus Monacrosporium thaumasium (NF34a) was used to produce the enzyme. The Plackett-Burman design was used in order to scan which components of the culture medium could have a significant influence on protease production by the fungus NF34a. An in vitro assay was also performed to evaluate the larvicidal activity of NF34a. It was observed that only one component of the culture medium (yeast extract), at the levels studied, had any significant effect (p < 0.05) on protease production. There was a reduction (p < 0.01) in the mean number of larvae recovered from the treated groups, compared with the control groups. The results confirm previous reports on the efficiency of nematophagous fungi for controlling nematode larvae that are potentially zoonotic. Thus, given the importance of biological control, we suggest that further studies should be conducted on the protease produced by the fungus Monacrosporium thaumasium.

O objetivo deste trabalho foi otimizar a produção de proteases do fungo nematófago Monacrosporium thaumasium (NF34a), avaliar sua atividade larvicida e sua estabilidade biológica. Foi utilizado um isolado do fungo nematófago Monacrosporium thaumasium (NF34a) para a produção de enzima. O delineamento Plackett-Burman foi utilizado com o objetivo de se escanear quais componentes do meio de cultura, poderiam ter influência significava na produção de protease pelo fungo NF34a. Foi realizado um ensaio in vitro para avaliar a atividade larvicida de NF34a. Observou-se que apenas um dos componentes do meio de cultura (extrato de levedura), nos níveis avaliados, apresentou um efeito significativo (p < 0,05) sobre a produção de protease. Houve redução (p < 0,01) entre as médias de larvas recuperadas dos grupos tratados em relação às dos grupos controle. Os resultados confirmam trabalhos anteriores da eficiência de fungos nematófagos no controle de larvas de nematóides potencialmente zoonóticos. Assim, devido a importância do controle biológico, os autores sugerem estudos mais aprofundados sobre a protease produzida pelo fungo Monacrosporium thaumasium.

In vitro differential activity of phospholipases and acid proteinases of clinical isolates of Candida / Atividade diferencial in vitro de fosfolipases e proteinases ácidas de isolados clínicos de Candida

INTRODUCTION: Candida yeasts are commensals; however, if the balance of normal flora is disrupted or the immune defenses are compromised, Candida species can cause disease manifestations. Several attributes contribute to the virulence and pathogenicity of Candida, including the production of extracellular hydrolytic enzymes, particularly phospholipase and proteinase. This study aimed to investigate the in vitro activity of phospholipases and acid proteinases in clinical isolates of Candida spp. METHODS: Eighty-two isolates from hospitalized patients collected from various sites of origin were analyzed. Phospholipase production was performed in egg yolk medium and the production of proteinase was verified in a medium containing bovine serum albumin. The study was performed in triplicate. RESULTS: Fifty-six (68.3 percent) of isolates tested were phospholipase positive and 16 (44.4 percent) were positive for proteinase activity. C. tropicalis was the species with the highest number of positive isolates for phospholipase (91.7 percent). Statistically significant differences were observed in relation to production of phospholipases among species (p<0,0001) and among the strains from different sites of origin (p=0.014). Regarding the production of acid protease, the isolates of C. parapsilosis tested presented a larger number of producers (69.2 percent). Among the species analyzed, the percentage of protease producing isolates did not differ statistically (χ2=1.9 p=0.5901 (χ2=1.9 p=0.5901). CONCLUSIONS: The majority of C. non-albicans and all C. albicans isolates were great producers of hydrolytic enzymes and, consequently, might be able to cause infection under favorable conditions.

INTRODUÇÃO: Candida são leveduras comensais, porém, se o equilíbrio da flora normal for interrompido ou as defesas imunitárias estiverem comprometidas, espécies de Candida podem causar manifestações de doença. Vários atributos contribuem na virulência e patogenicidade de Candida, inclusive a produção de enzimas extracelulares hidrolíticas, especialmente fosfolipases e proteinases. O objetivo deste estudo foi verificar a atividade in vitro de fosfolipases e proteinases ácidas em isolados clínicos de Candida spp. MÉTODOS: Oitenta e dois isolados provenientes de pacientes hospitalizados coletados a partir de sítios de origem diversos foram analisados. A produção de fosfolipase foi verificada em meio egg yolk e a de proteinase em meio contendo soro albumina bovina. O estudo foi feito em triplicata. RESULTADOS: Cinquenta e seis (68,3 por cento) dos isolados testados apresentaram atividade de fosfolipase positiva e 16 (44,4 por cento) foram positivos para atividade de proteinase. C. tropicalis foi a espécie que apresentou o maior número de isolados positivos para fosfolipases (91,7 por cento). Diferenças estatisticamente significantes em relação à produção de fosfolipases entre as espécies e entre as cepas provenientes de diferentes sítios de origem foram detectadas. Quanto à produção de proteinases ácidas, os isolados de C. parapsilosis testados foram os maiores produtores (69,2 por cento). Entre as espécies analisadas, a porcentagem de produção de proteinase entre os isolados não diferiu estatisticamente (χ2=1.9 p=0.5901 (χ2=1.9 p=0.5901). CONCLUSÕES: A maioria dos isolados de C. não-albicans, assim como os de C. albicans, foram grandes produtores de enzimas hidrolíticas e, consequentemente, podem ser capazes de causar infecção em condições adequadas.

Infecções oportunistas por leveduras e perfil enzimático dos agentes etiológicos / Opportunistic yeast infections and enzymatic profile of the etiological agents

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 por cento), seguido pelo trato urinário (10,5 por cento) 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.

Yeast infections are common in immunocompromised patients, although emerging species have been changing the epidemiological profile. The ability to secrete proteinases has been associated with pathogenicity within the genus Candida. This study had the aims of diagnosing yeast infections in immunocompromised patients and evaluating the virulence of the etiological agents, based on a proteinase secretion assay using bovine serum albumin as a substrate. Out of a total of 104 patients studied, 19 presented episodes of yeast infection. The respiratory tract (63.2 percent), followed by the urinary tract (10.5 percent), were the most common sites of infection. Candida albicans, Candida parapsilosis, Candida tropicalis and emerging species such as Candida krusei and Candida guilliermondii were isolated. Five isolates of Candida parapsilosis and one of Candida albicans and Candida guilliermondii exhibited high enzymatic activity. We conclude that enzymatic characterization of Candida isolates may be a useful prognostic marker, especially among immunocompromised individuals, since yeast infections in such patients are generally serious.

Viabilidade, confirmação taxonômica e detecção enzimática de espécies de Acremonium preservadas sob óleo mineral na Coleção de Culturas University Recife Mycology / Viability, taxonomic confirmation and enzymatic detection of Acremonium species preserved under mineral oil in the URM Culture Collection

Enzimas hidrolíticas secretadas por fungos têm um papel importante na patogenicidade das infecções. Objetivando avaliar a atividade enzimática foram testados 31 isolados de Acremonium mantidos na Coleção de Culturas University Recife Mycology. Fragmentos das culturas foram transferidos para caldo glicosado para reativação e posterior crescimento em meio ágar batata dextrose, para verificar viabilidade, pureza e confirmação taxonômica pela observação das características macroscópicas e microscópicas. Para detecção enzimática foram utilizados substratos de caseína do leite e gelatina para protease, amido para amilase e lecitina de soja para fosfolipase. Das 31 culturas, 26 (83,9 por cento) mantiveram-se viáveis e 24 (92,3 por cento) foram confirmadas taxonomicamente. Das 24 culturas, 12 (50 por cento) apresentaram atividade proteásica, duas (16,7 por cento) em caseína do leite, uma (8,3 por cento) em gelatina e nove (75 por cento) em ambos os substratos; 16 (66,7 por cento) degradaram amido. Nenhuma cultura apresentou atividade fosfolipásica. Conclui-se que espécies de Acremonium são capazes de produzir enzimas envolvidas na patogenicidade das infecções fúngicas.

Hydrolytic enzymes secreted by fungi play an important role in the pathogenesis of infection. With the aim of evaluating the enzymatic activity, 31 isolates of Acremonium stored in the University of Recife Mycology (URM) Culture Collection were tested. Culture fragments were transferred to glycoside broth for reactivation and further growth in potato dextrose agar medium in order to investigate viability and purity and to confirm the taxonomy through observing the macroscopic and microscopic characteristics. To detect enzymes, milk casein and gelatin were used as substrates for proteinase, starch for amylase and soy lecithin for phospholipase. Among the 31 cultures, 26 (83.9 percent) remained viable and 24 (92.3 percent) were confirmed taxonomically. Out of these 24 cultures, 12 (50 percent) presented proteinase activity, of which two (16.7 percent) were on milk casein, one (8.3 percent) on gelatin and nine (75 percent) on both substrates; 16 (66.7 percent) degraded starch. None of the cultures presented phospholipase activity. It was concluded that Acremonium species are able to produce enzymes that are involved in the pathogenicity of fungal infections.

Extracellular proteases from the Antarctic marine Pseudoalteromonas sp. P96-47 strain / Proteasas extracelulares de la cepa marina antártica Pseudoalteromonas sp. P96-47

The extracellular protease-production capacity of 33 bacterial isolates taken from marine biotopes in King George Island, Antarctica, was evaluated in liquid cultures. The P96-47 isolate was selected due to its high production capacity and was identified as Pseudoalteromonas sp. The optimal growth temperature was 20 °C and the optimal for protease production was 15 °C. Proteases were purified from culture supernatants, developing a multiple-band profile in zymograms. They were classified as neutral metalloproteases and worked optimally at 45 °C with an Eact of 47 kJ/ mol. Their stability was higher at neutral pH, retaining more than 80% of activity at pH 6-10 after 3 h incubation at 4 °C. After 90 min incubation at 40 and 50 °C, the percentages of residual activities were 78% and 44%. These results contribute to the basic knowledge of Antarctic marine proteases and also help evaluate the probable industrial applications of P96-47 proteases.

La capacidad productora de proteasas extracelulares de 33 aislamientos bacterianos tomados de biotopos marinos en la Isla Rey Jorge, Antártida, fue evaluada en cultivo líquido. El aislamiento P96-47 fue seleccionado debido a su alta capacidad productora y fue identificado como Pseudoalteromonas sp. La temperatura óptima de crecimiento fue de 20 °C y la de producción de 15 °C. Las proteasas fueron purificadas a partir del sobrenadante de cultivo, y en los zimogramas desarrollaron un perfil de múltiples bandas. Estas proteasas fueron clasificadas como metaloproteasas neutras y se observó que trabajan óptimamente a 45 °C, con una Eact de 47 kJ/ mol. Su estabilidad fue superior a pH neutro y retuvieron más del 80% de su actividad a pH 6-10 después de 3 h de incubación a 4 °C. Luego de 90 min de incubación a 40 y 50 °C, las actividades residuales fueron 78% y 44%, respectivamente. Los resultados que se presentan en este trabajo contribuyen al conocimiento básico de las proteasas marinas antárticas y también a evaluar las probables aplicaciones industriales de las proteasas de P96-47.

Enzymatic and hemolytic activities of Candida dubliniensis strains

Candida dubliniensis is an opportunistic yeast that has been recovered from several body sites in many populations; it is most often recovered from the oral cavities of human immunodeficiency virus-infected patients. Although extensive studies on epidemiology and phylogeny of C. dubliniensis have been performed, little is known about virulence factors such as exoenzymatic and hemolytic activities. In this study we compared proteinase, hyaluronidase, chondroitin sulphatase and hemolytic activities in 18 C. dubliniensis and 30 C. albicans strains isolated from AIDS patients. C. albicans isolates produced higher amounts of proteinase than C. dubliniensis (p < 0.05). All the tested C. dubliniensis strains expressed hyaluronidase and chondroitin sulphatase activities, but none of them were significantly different from those observed with C. albicans (p > 0.05). Hemolytic activity was affected by CaCl2; when this component was absent, we did not notice any significant difference between C. albicans and C. dubliniensis hemolytic activities. On the contrary, when we added 2.5 g percent CaCl2, the hemolytic activity was reduced on C. dubliniensis and stimulated on C. albicans tested strains (p < 0.05).

C. dubliniensis é uma levedura oportunista que, embora já tenha sido isolada de vários sítios anatômicos é, com maior frequência, encontrada na boca de pacientes infectados pelo HIV. Embora tenham sido realizados numerosos estudos sobre a epidemiologia e filogenia, seus fatores de virulência como atividade exoenzimática e atividade hemolítica, são, ainda, pouco conhecidos. Neste estudo comparou-se a atividade in vitro de proteinase, hialuronidase, condroitin sulfatase e atividade hemolítica de 18 cultivos de C. dubliniensis com 30 cultivos de C. albicans, todos isolados de pacientes com SIDA. Foi evidenciada maior atividade de proteinase em C. albicans em relação a C. dubliniensis (p < 0,05). Todos os isolados de C. dubliniensis evidenciaram atividade de hialuronidase e condroitin-sulfatase de forma similar ao observado com C. albicans (p > 0,05). Constatou-se que a atividade hemolítica foi influenciada pelo CaCl2; em sua ausência não foram observadas diferenças na atividade hemolítica das duas espécies; todavia, ao se agregar 2,5 por cento de CaCl2, a atividade hemolítica de C. dubliniensis foi reduzida enquanto a de C. albicans, estimulada (p < 0,05).

Biosynthesis of protease from Lactobacillus paracasei: kinetic analysis of fermentation parameters.

Fifteen strains of Lactobacillus species, isolated from different samples of curd were screened for their ability to produce more extracellular protease. The proteolytic activities of these strains based on casein hydrolysis showed a variation of 1.26-5.80 U ml(-l), with Lactobacillus IH8 showing the maximum activity and was identified as L. paracasei. Different cultural conditions for enhanced production of protease by L. paracasei were optimized. The optimal conditions for production of the enzyme were an incubation temperature of 35 degrees C and a medium pH of 6.0. The maximum proteolytic activity of L. paracasei (7.28 Uml(-1)) was achieved after 48 h of cultivation. The kinetic parameters such as product yield (Yp/x,), growth yield (Yx/s), specific product yield (qp) and specific growth yield (qs) coefficients also revealed that the values of experimental results were kinetically significant.

Phenotypic aspects of oral strains of Candida albicans in children with down's syndrome / Aspectos fenotípicos de cepas de Candida albicans orais em crianças com síndrome de down

The aim of this article is to characterize the biological aspects of oral strains of C. albicans in children with Down's syndrome. These yeasts were analyzed as to their macromorphological and enzymatic aspects and were tested as to their in vitro susceptibility to antifungal drugs using broth microdilution to determine the minimum inhibitory concentration (MIC). The morphotyping revealed that all oral C. albicans isolates from children with Down's syndrome promoted the formation of fringes regardless of size, while the control group presented smaller fringes. All oral C. albicans strains produced proteinase, but those with phospholipolytic activity showed greater enzyme capacity in the test group. In vitro susceptibility showed that all oral C. albicans isolates were sensitive to the drugs used.

O objetivo deste artigo foi caracterizar os aspectos biológicos de cepas de C. albicans orais em crianças com síndrome de Down. Estas leveduras foram analisadas quanto aos seus aspectos macromorfológicos e enzimáticos e foram testadas quanto a sua suscetibilidade in vitro a drogas antifúngicas, usando a microdiluição em caldo para a determinação da concentração inibitória mínima (CIM). A morfotipagem revelou que todos os isolados de C. albicans orais de crianças com síndrome de Down induziram à formação de franjas independente do tamanho, enquanto o grupo controle teve franjas menores. Todas as cepas de C. albicans orais produziram proteinase, mas aquelas com atividade fosfolipidolítica mostraram maior capacidade enzimática no grupo teste. A suscetibilidade in vitro mostrou que todos os isolados de C. albicans orais foram sensíveis a drogas empregadas.

Influence of nutritional supplements on keratinolysis by Amycolatopsis keratinophila.

Keratinolytic potential of A. keratinophila (DSM 44409T), a newly described Amycolatopsis sp. isolated from cultivated soil in Kuwait, was demonstrated using keratinazure as the sole source of carbon and nitrogen as estimated by gel diffusion assay. Effects of 12 various nutritional supplements on the keratinolytic and azocollytic activities were determined. NH4H2PO4 and KNO3 in the medium supported a significantly higher keratinolytic activity than other supplements. However, azocollytic activities in all the supplemented media and the control were same. Best combination of carbon and nitrogen supplements (galactose and NH4H2PO4 respectively) used to evaluate the dynamics of growth and enzymes (keratinase and protease) activities of the isolate revealed a luxuriant growth with optimal keratinolytic activity occurring during the log phase. Other parameters of the fermentation medium, including pH, biomass accumulation, total protein and free amino acid concentrations were also studied.

Partial characterization of acidic proteinase in the midgut of parasarcophaga surcoufi larvae [Diptera: Sarcophagidae]

Activity of acidic proteinase in the midgut of larval Parasarcophaga surcoufi was investigated and partially characterized. Larval midgut extract showed a moderate acidic pH [pH 4] optimum for hydrolysis of hemoglobin. The proteolytic activity of the larval midgut was estimated by hydrolysis of hemoglobin and was found to be inhibited by pepstatin [aspartic proteinase inhibitor], dithiothreitol [DTT] and mercaptoethanol, while it was not inhibited by soybean trypsin inhibitor [STI] and EDTA. These characteristics may imply that cathepsin D-like proteinase is an effective acidic proteinase present in the Parasarcophaga surcoufi larval midgut

effect of some inducers and inhibitors on protease production by bacillus cereus

Batch cultures of Bacillus cereus grew most luxuriantly with 3% glucose [w/v], 2% tryptone, 0.5% K2HSO4 and 1 mg/ml MnCl2H2O, supplemented to the basal medium with high enzyme activity [biomass 3.06 g/100 ml and enzyme activity 57.19 U/ml, with specific activity 39.44 U/mg protein]. All the tested nitrogen sources, ascorbic acid, ATP, chloramphenicol and vitamins exerted a significant decrease in the enzyme production

Proteolytic activity saccharomyces cerevisiae as affected by cultural conditions.1-Effect of certain environmental conditions

The protelytic activity of S. cerevisiae was studied under the influence of some environmental and cultural conditions. The optimum temperature necessary for maximum proteolytic activity was 30§, the optimum incubation period was 5 days, the optimum pH value was 5. Maximum biomass yield and proteolytic activity was given at 0.5 g/1 NaCl concentration. 5 g/1 of glucose gave maximum biomass yield, but the maximal proteolytic activity was attained in culture media free from sugar content. Effect of shaking was studied. The agitated cultures gave growth parameters and proteolytic activity much more than the static cultures