Abstract:
:We present herein an improved assay for detecting the presence of extracellular proteases from microorganisms on agar plates. Using different substrates (gelatin, BSA, hemoglobin) incorporated into the agar and varying the culture medium composition, we were able to detect proteolytic activities from Pseudomonas aeruginosa, Micrococcus luteus and Serratia marcescens as well as the influence that these components displayed in the expression of these enzymes. For all microorganisms tested we found that in agar-BHI or yeast extract medium containing gelatin the sensitivity of proteinase detection was considerably greater than in BSA-agar or hemoglobin-agar. However, when BSA or hemoglobin were added to the culture medium, there was an increase in growth along with a marked reduction in the amount of proteinase production. In the case of M. luteus the incorporation of glycerol in BHI or yeast extract gelatin-agar induced protease liberation. Our results indicate that the technique described here is of value for detecting extracellular proteases directly in the culture medium, by means of a qualitative assay, simple, inexpensive, straight forward method to assess the presence of the proteolytic activity of a given microorganism colony with great freedom in substrate selection.
journal_name
Mem Inst Oswaldo Cruzjournal_title
Memorias do Instituto Oswaldo Cruzauthors
Vermelho AB,Meirelles MN,Lopes A,Petinate SD,Chaia AA,Branquinha MHdoi
10.1590/s0074-02761996000600020subject
Has Abstractpub_date
1996-11-01 00:00:00pages
755-60issue
6eissn
0074-0276issn
1678-8060pii
S0074-02761996000600020journal_volume
91pub_type
杂志文章abstract::The diagnosis of tick-borne diseases such as babesiosis still depends on observing the parasite in the infected erythrocyte. Microscopic observation is tedious and often problematic in both early and carrier infections. Better diagnostic methods are needed to prevent clinical disease, especially when susceptible cattl...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章,评审
doi:10.1590/s0074-02761992000700032
更新日期:1992-01-01 00:00:00
abstract::A case-control study was conducted to determine the presence ofMycobacterium lepraeDNA in nasal secretions of leprosy cases and nonleprosy individuals in Fortaleza, Brazil. It included 185 cases identified by physicians at the Dona Libânia National Reference Centre for Sanitary Dermatology (CDERM). A control group (Co...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/0074-02760150178
更新日期:2015-11-01 00:00:00
abstract::The diagnosis of human cutaneous leishmaniasis in small towns is sometimes made without the species identification of the Leishmania, even in areas without previous epidemiological surveys. Here we report the isolation of a Leishmania strain from a patient of Rincão, state of São Paulo, that was identified by isoenzym...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02762005000700009
更新日期:2005-11-01 00:00:00
abstract:BACKGROUND:Cutaneous leishmaniasis (CL) generally presents with a single or several localised cutaneous ulcers without involvement of mucous membranes. Ulcerated lesions are susceptible to secondary contamination that may slow the healing process. OBJECTIVE:This study verified the influence of non-parasitic wound infe...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/0074-02760160557
更新日期:2017-09-01 00:00:00
abstract::The cellular nature of the infiltrate in cutaneous lesion of rhesus monkeys experimentally infected with Leishmania (L.) amazonensis was characterized by immunohistochemistry. Skin biopsies from infected animals with active or healing lesions were compared to non-infected controls (three of each type) to quantitate in...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02762000000200012
更新日期:2000-03-01 00:00:00
abstract::Clinical and laboratory evidence is reviewed which shows that there is a great deal of variation in the susceptibility of Schistosoma mansoni to oxamniquine. This variation occurs both among endemic regions and within endemic regions in Brazil and Kenya. It is genetically controlled. It is suggested that the parasite ...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02761987000800026
更新日期:1987-01-01 00:00:00
abstract::We have been interested in identifying genes that play a role in reproduction of the mosquito Aedes aegypti. Our interests are currently focused on the vitellogenin genes which in the mosquito are expressed only in the fat body in response to the insect steroid hormone, 20-hydroxyecdysone. Four of the five vitellogeni...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02761987000700021
更新日期:1987-01-01 00:00:00
abstract::Resistance in Mycobacterium tuberculosis to isoniazid (INH) is caused by mutations in the catalase-peroxidase gene (katG), and within the inhA promoter and/or in structural gene. A small percentage (approximately 10%) of INH-resistant strains do not present mutations in both of these loci. Other genes have been associ...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02762007000100009
更新日期:2007-02-01 00:00:00
abstract::BACKGROUND Human herpesvirus 2 (HHV-2) have DNA genome with a limited genetic variability and have been classified into two clades. OBJECTIVES To identify and characterise six HHV-2 isolates derived from Brazilian women. METHODS HHV-2 isolates were performed polymerase chain reaction (PCR) and sequencing of 2250 pb of...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/0074-02760180328
更新日期:2018-12-03 00:00:00
abstract::Toxoplasma gondii has a very wide intermediate host range and is thought to be able to infect all warm blooded animals. The parasite causes a spectrum of different diseases and clinical symptoms within the intermediate hosts and following infection most animals develop adaptive humoral and cell-mediated immune respons...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章,评审
doi:10.1590/s0074-02762009000200018
更新日期:2009-03-01 00:00:00
abstract::Leptospirosis in humans usually involves hypokalaemia and hypomagnesaemia and the putative mechanism underlying such ionic imbalances may be related to nitric oxide (NO) production. We previously demonstrated the correlation between serum levels of NO and the severity of renal disease in patients with severe leptospir...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/S0074-0276108042013007
更新日期:2013-06-01 00:00:00
abstract::The objective of this study was to evaluate the feeding behavior of Triatoma vitticeps through the identification of its food sources and the characterization of the blood ingestion process. In addition, we aimed to verify if the saliva of this vector interferes with the perception of the host during the feedings by c...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02762011000100003
更新日期:2011-02-01 00:00:00
abstract::In previous studies it was shown that the recombinant molecule, r-Sm14, induces high levels of protection against Schistosoma mansoni infection in two outbred animal models and immune crossprotection against infection by Fasciola hepatica in Swiss outbred mice. r-Sm14 was derived from a living worm extract, called SE,...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02762001000900011
更新日期:2001-01-01 00:00:00
abstract::The hepatitis C virus (HCV) can be detected in blood and other bodily fluids, such as saliva, semen and gastric juices. The aim of this study was to compare the HCV viral loads in the serum and saliva of infected patients. Twenty-nine patients with detectable HCV RNA in their serum and saliva were included in this stu...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02762012000500016
更新日期:2012-08-01 00:00:00
abstract::Experiments with Squamatoides trivitattus were carried out in two different controlled temperatures (16 +/- 1 degree C/50-60% RH and 27 +/- 1 degree C/70-80% RH). The viability of larvae and pupae at 27 degrees C was 89.82% and 92.75% respectively. Larvae did not develop at 16 degrees C. Larval development lasted for ...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02761996000200024
更新日期:1996-03-01 00:00:00
abstract::For the first time, a jar of embalming rejects was studied in search for helminth parasite eggs. This kind of jar was used to put discarded material by Egyptian embalmers during mummification process. Ascaris lumbricoides and Taenia saginata eggs were found in the linen and strip fragment contents of the jar, dated of...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02762003000900017
更新日期:2003-01-01 00:00:00
abstract::Sixty eight patients with localized cutaneous leishmaniasis from an area with Leishmania (Viannia) braziliensis transmission had cultures performed with a modified Marzochís vacuum aspiratory puncture technique to establish sensitivity and contamination rate with this new method. Overall sensitivity of three aspirates...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02761999000400014
更新日期:1999-07-01 00:00:00
abstract::Details are given of the prevalence rates of onchocerciasis from the most recent surveys (1989) conducted in northern Ecuador. The disease has intensified and dispersed considerably due to migration of infected individuals and the presence of a highly efficient vector. Comparison of these data with those from two prev...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02761992000300011
更新日期:1992-07-01 00:00:00
abstract::The black flies of the genus Inaequalium present a Neotropical distribution, with Panama at the northern limit, and the Argentinian pampas at the southern, but do not occur in the Central Amazon. This study offers a cladistic analysis establishing a hypothesis of relationships between the species of Inaequalium. A tot...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02762002000100010
更新日期:2002-01-01 00:00:00
abstract:BACKGROUND:Since the early 1990s, programs to control Chagas disease in South America have focused on eradicating domiciliary Triatoma infestans, the main vector. Seroprevalence studies of the chagasic infection are included as part of the vector control programs; they are essential to assess the impact of vector contr...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/0074-02760160407
更新日期:2017-05-01 00:00:00
abstract::Living in close association with a vertebrate host and feeding on its blood requires different types of adaptations, including behavioural adjustments. Triatomines exhibit particular traits associated with the exploitation of their habitat and food sources and these traits have been the subject of intense analysis. Ma...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02762009000900011
更新日期:2009-07-01 00:00:00
abstract::From 1970 to 1982, 884 cases of human leptospirosis were serologically diagnosed at the Leptospirosis Laboratory, Fundação Oswaldo Cruz - FIOCRUZ, by means of the microscopic agglutination test. Of these patients, 775 were hospitalized in the city of Rio de Janeiro, and 109 were reported by other Brazilian cities. Ict...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02761987000100016
更新日期:1987-01-01 00:00:00
abstract::Mycobacteria, specially Mycobacterium tuberculosis are among the micro-organisms that are increasing dramatically the number of infections with death, all over the world. A great number of animal experimental models have been proposed to investigate the mechanisms involved in the host response against these intracellu...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章,评审
doi:10.1590/s0074-02761997000800033
更新日期:1997-01-01 00:00:00
abstract::Only one drug is currently available for the treatment and control of schistosomiasis and the increasing risk of selecting strains of schistosome that are resistant to praziquantel means that the development of new drugs is urgent. With this objective we have chosen to target the enzymes modifying histones and in part...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02762011000700003
更新日期:2011-11-01 00:00:00
abstract::Lymphatic filariasis caused by nematode parasites Wuchereria bancrofti or Brugia malayi is a spectral disease and produces wide range of immune responses and varying levels of microfilaraemia in infected individuals. The relationship between the immune response of host and the developmental stage of the parasite as we...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02762006000300007
更新日期:2006-05-01 00:00:00
abstract::We have initiated a gene discovery program in Schistosoma mansoni based on the technique of Expressed Sequence Tags (ESTs), i.e. partial sequences of cDNAs obtained from single passes in automatic DNA sequences. ESTs can be used to identify genes on the basis of their homology with sequences from other species deposit...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02761995000200015
更新日期:1995-03-01 00:00:00
abstract:BACKGROUND:Increasing evidence suggests that human papillomavirus (HPV) intratype variants (specific lineages and sublineages) are associated with pathogenesis and progression from HPV infection to persistence and the development of cervical cancer. OBJECTIVES:This study aimed to verify the prevalence of HPV infection...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/0074-02760160530
更新日期:2017-07-01 00:00:00
abstract::The seroprevalence of toxoplasmosis in 832 pregnant women in Miracema, Rio de Janeiro, was determined and 75.1% (625) and 2.0% (17) were anti-Toxoplasma gondii IgG and IgM positive, respectively. Out of the 17 IgM positive pregnant women, only one had low avidity IgG corresponding to the acute phase of the infection. ...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02762008000600013
更新日期:2008-09-01 00:00:00
abstract::Three Yersinia pestis strains isolated from humans and one laboratory strain (EV76) were grown in rich media at 28 degrees C and 37 degrees C and their outer membrane protein composition compared by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Several proteins with molecular weights ranging f...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章
doi:10.1590/s0074-02761990000100018
更新日期:1990-01-01 00:00:00
abstract::Facilitated and improved by advances in molecular biology, techniques for the immunodiagnosis of schistosomiasis, including assays based on the detection of antigens circulating in the serum and/or excreted in the urine, have now reached the stage of multi-centre trials. There is a need to complement parasitological t...
journal_title:Memorias do Instituto Oswaldo Cruz
pub_type: 杂志文章,评审
doi:10.1590/s0074-02761992000800004
更新日期:1992-01-01 00:00:00