Solubilization, Activation and Partial Purification of a Sialidase from Horse Liver

Using sialyl-methylumbelliferyl -glycoside as substrate, sialidase in horse liver was detected as a membrane-bound enzyme. A yield of about 50% of sialidase activity was found in supernatant when solubilized in 0.1 M sodium-phosphate buffer pH 5.5, containing 0.15 M NaCl, 0.25 M sucrose, and 0.5% Triton X-100. Sialidase in the solubilisate could be activated by incubating in acidic pH at 37 oC. Incubation of this solubilized enzyme at 37 oC for 1.5 h at pH 5.0 led to 10% increase of activity and to the precipitation of about 50% of contaminating protein. Using cation-exchange chromatography on S-Sepharose FF and affinity chromatography on p-aminophenyl oxamic acid-agarose following solubilization and activation, about 6% of total sialidase activity was recovered with the purification factor of about 500. The pH and temperature optimum were measured at pH 4.3 and between 37-45 oC, respectively. Neu5Ac2en was a strong inhibitor, while p-aminophenyl oxamic acid had only a weak inhibitory effect

Solubilization, Activation and Partial Purification of a Sialidase from Horse Liver

Using sialyl-methylumbelliferyl α-glycoside as substrate, sialidase in horse liver was detected as a membrane-bound enzyme. A yield of about 50% of sialidase activity was found in supernatant when solubilized in 0.1 M sodium-phosphate buffer pH 5.5, containing 0.15 M NaCl, 0.25 M sucrose, and 0.5% Triton X-100. Sialidase in the solubilisate could be activated by incubating in acidic pH at 37 °C. Incubation of this solubilized enzyme at 37 °C for 1.5 h at pH 5.0 led to 10% increase of activity and to the precipitation of about 50% of contaminating protein. Using cation-exchange chromatography on S-Sepharose FF and affinity chromatography on p-aminophenyl oxamic acid-agarose following solubilization and activation, about 6% of total sialidase activity was recovered with the purification factor of about 500. The pH and temperature optimum were measured at pH 4.3 and between 37-45 °C, respectively. Neu5Ac2en was a strong inhibitor, while p-aminophenyl oxamic acid had only a weak inhibitory effect

Babies and bearded dragons: sudden increase in reptile-associated Salmonella enterica serovar Tennessee infections, Germany 2008

Introduction: In 2008 a marked increase in Salmonella enterica serovar Tennessee infections in infants occurred in Germany. In March and April 2008, eight cases were notified compared to a median of 0–1 cases in 2001–2006. Materials and Methods: We carried out an investigation including a case–control study to identify the source of infection. A patient was a chil

Pet Snakes as a Reservoir for Salmonella enterica subsp. diarizonae (Serogroup IIIb): a Prospective Study

Reptile-associated Salmonella infections are an increasing problem for humans. We have prospectively screened two breeding groups of 16 pet snakes for colonization with Salmonella species. Various serovars of S. enterica subsp. diarizonae were found in 81% of the snakes. To avoid transmission, strict hygienic precautions should be applied when reptiles are handled

Salmonella Agona Outbreak from Contaminated Aniseed, Germany

A nationwide outbreak of Salmonella Agona caused by aniseed-containing herbal tea occurred from October 2002 through July 2003 among infants in Germany. Consumers should adhere strictly to brewing instructions, although in exceptional cases this precaution may not be protective, particularly when preparing tea for vulnerable age groups

Sequence-Based Typing of flaB Is a More Stable Screening Tool Than Typing of flaA for Monitoring of Campylobacter Populations

Different typing schemes for Campylobacter spp. were evaluated with 70 outbreak and sporadic isolates. The discriminatory indexes were 0.944 (by pulsed-field gel electrophoresis), 0.920 (by genotyping of the flagellin A gene), 0.902 (by genotyping of flaB), and 0.886 (by multilocus sequence typing). Cross-classification gave 94.77 or 95.82% (PFGE-flaA or PFGE-flaB) concordance. flaA was overdiscriminatory in three cases, most probably due to intragenomic recombination

Supplement 2003–2007 (No. 47) to the White-Kauffmann-Le Minor scheme

International audienceThis supplement reports the characterization of 70 new Salmonella serovars recognized between 2003 and 2007 by the WHO Collaborating Center for Reference and Research on Salmonella: 44 were assigned to Salmonella enterica subspecies enterica, 11 to subspecies salamae, 5 to subspecies arizonae, 8 to subspecies diarizonae, one to subspecies houtenae and one to Salmonella bongori. One new serovar, Mygdal, displayed a new H factor, H:z(91)

Infektionen des Menschen durch enterohämorrhagische Escherichia coli (EHEC) in der Bundesrepublik Deutschland von 1998 bis 2001

In der Bundesrepublik Deutschland weisen die intestinalen Infektionen mit enterohämorrhagischen Escherichia coli (EHEC) in den Jahren von 1998 bis 2001 eine außerordentlich große biologische Erregervielfalt auf. Es zeigt sich jedoch keine dramatische Zunahme ihrer klinischen und epidemiologischen Bedeutung. Während Infektionen mit dem Serovar O157:H7 weiter rückläufig sind, treten zunehmend andere EHEC-Erregergruppen wie O26:H11 und O1O3:H2 u.a. als Infektionsursachen auf. Diese große Erregervielfalt weist möglicherweise auf vielfältige Infektionsquellen und -wege hin. Da inzwischen weitere bakterielle Pathogenitätsfaktoren identifiziert wurden (besonders durch die Entschlüsselung des EHEC-Genoms), ist die Differenzierung von humanpathogenen und nicht humanpathogenen Stämmen weiterhin offen. Eine kontinuierliche Überwachung dieser Erregervielfalt und -dynamik, ihrer Ausbreitung und ihrer Infektionswege sowie -quellen bleibt eine wichtige Aufgabe des öffentlichen Gesundheitsdienstes (ÖGD).Intestinal infections in Germany due to enterohemorrhagic E. coli bacteria (EHEC) between 1998 and 2001 reveal a large scale of biological diversity of their pathogens. However, no dramatic increase of their clinical importance and public health implications has been observed. As strains of serovar O157:H7 have continuously declined as causative agents, other serovars such as O26:H11 and O103:H2 have replaced them. The great diversity of the EHEC pathogens might point to a great number of various infection routes and sources. Since recently new pathogenic factors of EHEC bacteria have been detected (especially by the sequencing of the genome of EHEC), it is currently not possible to define a clear-cut difference between human pathogens and nonhuman pathogens. The enhanced surveillance of EHEC pathogens with respect to their biological diversity and dynamics, their epidemic spread, and their infection routes and sources remain an essential task of the public health authorities

Supplement 2008-2010 (no. 48) to the White-Kauffmann-Le Minor scheme.

International audienceThis supplement (no. 48) of the White-Kauffmann-Le Minor scheme reports on the characterization of 63 new Salmonella serovars and 25 new variants of previously described Salmonella serovars recognized by the WHO Collaborating Centre for Reference and Research on Salmonella between 2008 and 2010. Forty-four new serovars were assigned to Salmonella enterica subspecies enterica, 12 to subspecies salamae, two to subspecies arizonae, two to subspecies diarizonae and three to subspecies houtenae. All these new serovars or new variants are described with their multilocus sequence type