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1.
Vox Sang ; 119(4): 308-314, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38226700

RESUMEN

BACKGROUND AND OBJECTIVES: In addition to mandatory testing of blood donations, the deferral of donors in the case of various sexual and non-sexual risk exposures ensures the safety of blood products in Germany. The study aimed to quantify non-disclosure of non-sexual risk exposures, as no data are available so far. MATERIALS AND METHODS: We conducted an anonymous online survey among whole-blood donors with successful donations between January and March 2020. Data on travel to countries with endemic malaria, recent mild or febrile infections, tattoos or piercings and drug use were collected. We analysed non-compliance in relation to donor demographics by multivariable analyses. RESULTS: Altogether, 5.4% of the donors were non-compliant. Non-disclosure was highest for mild infection with 3.3% of donors, followed by febrile infections (1.4%), travel to malaria endemic countries (0.7%) and body modifications (0.5%). Intravenous drug use was negligible in our study population. Age was a predictor for all investigated risks, with higher prevalence in younger age groups. Prevalence ratios for non-disclosure of body modifications and mild infection were higher in females than males. Donation in blood establishments with mobile services was associated with higher non-disclosure of mild infections. CONCLUSION: The considerable degree of non-compliance in some donor groups reflects the prevalence of risk factors in the underlying population (e.g., body modification) as well as probable tendency to socially desirable responding. Donor education should not focus exclusively on sexual risk behaviour, as undisclosed non-sexual exposures may bear risks for recipients and donors.


Asunto(s)
Malaria , Tatuaje , Masculino , Femenino , Humanos , Donantes de Sangre , Factores de Riesgo , Conducta Sexual
2.
Transfus Med Hemother ; 49(6): 368-378, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36654976

RESUMEN

Background: Undisclosed sexual infection risks are the main reasons for transfusion transmissible infections in German blood donors that have qualified for donation by donor health interviews and questionnaires. Until now, data about compliance with deferral criteria were only available from post-donation interviews with infected donors, and information about the proportion of donors which did not disclose (sexual) risks at the donor health questionnaire was not available. Methods: A prospective nationwide anonymous online survey was conducted to investigate compliance of whole blood donors with deferral criteria for sexual infection risks. Twenty-one blood establishments which represent 80% of the regular whole blood-donor population invited all donors which donated blood during an 8-week period between January and March 2020. Results: 14,882 participants completed the questionnaire. A relevant proportion of non-compliance was shown (3.0%, 95% CI: 2.7-3.3%) - with male donors being non-compliant significantly more frequently than females (3.5% vs. 2.2%, p < 0.001). A quarter of the non-compliant men were MSM (0.9%, 95% CI: 0.7-1.1%). Non-compliance was strongly associated with the perception that questions about sexual risk exposures are too private. This is in line with the finding that a large proportion of donors (21%) refused to answer at least one question about sexual infection risks. Conclusion: The presented data, collected for the first time, is suitable for assessing the impact of changes in the donor selection process. Donor's limited willingness to provide detailed information about sexual risk behaviour has to be kept in mind when further strategies for fair appraisal of individual sexual infection risks will be discussed.

3.
Transfus Med Hemother ; 49(4): 192-204, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36159956

RESUMEN

West Nile virus (WNV) is an arthropod-borne virus (arbovirus). It circulates in an enzootic cycle between ornithophilic mosquitoes as vectors and reservoirs and avian host species for amplification, but humans can be infected as accidental hosts. In most individuals, WNV infection remains silent, while 20% develop mild symptoms of West Nile fever, and only 1% develop neuroinvasive disease (WNND). Human WNV cases have been identified in Southern and Eastern Europe for more than 20 years, but until 2018, Germany was considered to be a non-endemic country. This changed when in the exceptionally warm summer of 2018, conditions for viral replication in mosquitoes were ideal, and the first WNV cases among birds and horses were identified. The widespread domestic Culex mosquitoes are efficient vectors for WNV. Autochthonous mosquito-borne WNV infections in humans were reported in all following years, indicating a continuous circulation in the affected areas of Central-East Germany. So far, no clear expansion of the affected areas is discernible but may develop. WNV is a transfusion-transmissible-infection, and donor deferral or testing of donations after a stay in an affected area are effective means to ensure transfusion safety. WNV transmissions via blood products often result in WNND due to the predisposing underlying medical conditions of transfusion recipients. From 2020 onwards, roughly 80% of all blood establishments in Germany tested their donations for WNV using nucleic acid amplification techniques in the transmission season. Altogether, 19 confirmed WNV infections were identified from 2020-2021. As long as effective and affordable pathogen reduction is not available for all blood components, WNV testing or donor deferral will be essential. In order to timely identify affected areas, combined results of human and veterinary surveillance are needed. Partnerships between public health experts, transfusion medicine specialists, veterinarians, and entomologists should be strengthened to ensure a One Health approach.

4.
Transfus Med Hemother ; 45(2): 108-114, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29765294

RESUMEN

BACKGROUND: Potential risks for transfusion-transmissible infections are identified by donor history questionnaires (DHQs), and donors with higher risks are deferred from donation. We assessed to which extent the currently used DHQs support the identification of infections among blood donors. METHODS: Between 2006 and 2013, we analyzed data from notified HIV and HCV cases in the general population and positive blood donors in Germany. Logistic regressions were used to identify relevant infection risks. We estimated the possible effect of improved capture of risk factors for donor selection by calculation of population attributable fractions (PAF). RESULTS: Risky sexual contacts - MSM as well as heterosexual contacts - were the most prominent infection risks among HIV-infected donors. Whereas MSM contacts were significantly less reported by donors than by cases from the general population, 58% of donors disclosed heterosexual risks compared to 26% of notified cases. The complete identification of heterosexual risk contacts might prevent acceptance of 53% of HIV-infected donors. HCV-infected donors were more likely to report heterosexual exposure, imprisonment, and piercing/tattoo than notified HCV cases. Improved recording of piercing/tattoo could prevent acceptance of 16% of HCV-infected donors. CONCLUSION: Donor selection should be improved with special attention to the identification of (hetero)sexual risk factors, invasive procedures (piercing/tattoo and imprisonment) applying well-designed DHQs, effective donor education, and confidential environment in all steps of the selection process.

6.
BMC Infect Dis ; 15: 88, 2015 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-25879490

RESUMEN

BACKGROUND: During weeks 32-33, 2013, 24 cases of cryptosporidiosis were notified in the city of Halle (annual mean 2008-2012: 9 cases). We investigated the outbreak to identify the source and recommend control measures, considering that between weeks 23-25 the river Saale which flows through the city centre overflowed the floodplain, parts of the city centre and damaged sewage systems. METHODS: We defined a case as a resident of Halle with gastroenteritis, Cryptosporidium-positive stool and disease onset weeks 27 through 47. In a case-control study among kindergarten children, we compared cases and controls regarding environmental exposure, use of swimming pools, zoo visits and tap water consumption 14 days pre-onset or a corresponding 14-days-period (controls) and adjusted for residence. Stool specimens were tested by microscopy and PCR, and Cryptosporidium DNA was sequenced. Samples from public water system, swimming pools and river Saale were examined for Cryptosporidium oocysts (microscopy and PCR). RESULTS: Overall, 167 cases were detected, 40/167 (24%) were classified as secondary cases. First disease onsets occurred during week 29, numbers peaked in week 34 and started to decrease in week 36. Median age was 8 years (range: 0-77). Compared to controls (n = 61), cases (n = 20) were more likely to report visits to previously flooded areas (OR: 4.9; 95%-CI: 1.4-18) and the zoo (OR: 2.6; 95%-CI: 0.9-7.6). In multivariable analysis visits to the floodplain remained the sole risk factor (OR: 5.5; 95%-CI: 1.4-22). Only C.hominis of a single genotype (IbA9G2) was detected in stools. Oocysts were detected in samples from the river, two local lakes and three public swimming pools by microscopy, but not in the public water supply. CONCLUSIONS: Evidence suggests that activities in the dried out floodplain led to infection among children. Secondary transmissions may be involved. Consequently, authorities recommended to avoid playing, swimming and having picnics in the flood-affected area. Health authorities should consider the potential health risks of long-term surviving parasites persisting on flooded grounds and in open waters even several weeks after the flooding and of bathing places close to sewage spill-overs. Preventive measures comprise water sampling (involving parasites), information of the public and prolonged closures of potentially contaminated sites.


Asunto(s)
Criptosporidiosis/epidemiología , Inundaciones , Ríos , Adolescente , Adulto , Anciano , Animales , Estudios de Casos y Controles , Niño , Preescolar , Criptosporidiosis/parasitología , Cryptosporidium/aislamiento & purificación , Brotes de Enfermedades , Femenino , Inundaciones/estadística & datos numéricos , Gastroenteritis/epidemiología , Gastroenteritis/parasitología , Alemania/epidemiología , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Ríos/parasitología , Piscinas , Abastecimiento de Agua , Adulto Joven
7.
Vector Borne Zoonotic Dis ; 24(6): 396-401, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38573211

RESUMEN

Background: Autochthonous human West Nile virus (WNV) infections were notified in the infectious disease surveillance system in Germany in 2018 for the first time and every year since then. Since clinically apparent infections are infrequent, we conducted two studies to investigate subclinical infections of this emerging disease in Germany in 2019 to detect infections not visible to surveillance based on symptomatic infections: limited-scope blood donor testing and a serosurvey among employees at two Berlin zoos with a history of demonstrated WNV infections in animals. Methods: For the zoo study, employees of the two zoos in Berlin were invited to participate in the study in late 2019. Blood samples were drawn and tested for the presence of antibodies (immunoglobulin M [IgM] and immunoglobulin G [IgG]) against WNV, and two other flaviviruses present in Germany: Usutu virus and Tick-borne encephalitis virus (TBEV). For the study in blood donors, four blood establishments with collection sites in regions with documented WNV-infected animals in 2018 and 2019 participated in the study. All donations in these regions were tested for WNV genome from July to November 2019. Results: In the enzyme-linked immunosorbent assay, none of the 70 tested zoo employees were WNV IgM-positive, 8 were WNV IgG-positive, additional 2 participants had equivocal results. All 10 were negative in the virus neutralization test (VNT) for WNV, but positive in the VNT for TBEV. None of the 4273 samples from blood donors tested in areas with WNV-infected animals was positive for WNV-RNA. Conclusion: Our results indicate that WNV circulation in Germany, though clearly documented in animals in 2019, apparently affected very few humans. Still areas with WNV-positive animals remain risk areas for human infection as well.


Asunto(s)
Anticuerpos Antivirales , Fiebre del Nilo Occidental , Virus del Nilo Occidental , Humanos , Fiebre del Nilo Occidental/epidemiología , Fiebre del Nilo Occidental/veterinaria , Fiebre del Nilo Occidental/virología , Virus del Nilo Occidental/aislamiento & purificación , Virus del Nilo Occidental/inmunología , Alemania/epidemiología , Animales , Anticuerpos Antivirales/sangre , Donantes de Sangre , Masculino , Animales de Zoológico , Femenino , Adulto , Persona de Mediana Edad , Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/veterinaria , Enfermedades Transmisibles Emergentes/virología , Inmunoglobulina G/sangre , Estudios Seroepidemiológicos
8.
Pathogens ; 12(4)2023 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-37111436

RESUMEN

SARS-CoV-2 serosurveillance is important to adapt infection control measures and estimate the degree of underreporting. Blood donor samples can be used as a proxy for the healthy adult population. In a repeated cross-sectional study from April 2020 to April 2021, September 2021, and April/May 2022, 13 blood establishments collected 134,510 anonymised specimens from blood donors in 28 study regions across Germany. These were tested for antibodies against the SARS-CoV-2 spike protein and nucleocapsid, including neutralising capacity. Seroprevalence was adjusted for test performance and sampling and weighted for demographic differences between the sample and the general population. Seroprevalence estimates were compared to notified COVID-19 cases. The overall adjusted SARS-CoV-2 seroprevalence remained below 2% until December 2020 and increased to 18.1% in April 2021, 89.4% in September 2021, and to 100% in April/May 2022. Neutralising capacity was found in 74% of all positive specimens until April 2021 and in 98% in April/May 2022. Our serosurveillance allowed for repeated estimations of underreporting from the early stage of the pandemic onwards. Underreporting ranged between factors 5.1 and 1.1 in the first two waves of the pandemic and remained well below 2 afterwards, indicating an adequate test strategy and notification system in Germany.

9.
Toxicon ; 47(2): 156-62, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16356522

RESUMEN

Three single-filament isolates of Aphanizomenon flos-aquae from two German lakes were found to produce remarkable amounts of the cyanobacterial hepatotoxin cylindrospermopsin (CYN). CYN-synthesis of the strains were evidenced both by LC-MS/MS analysis and detection of PCR products of gene fragments which are implicated in the biosynthesis of the toxin. The strains contain CYN in the range of 2.3-6.6 mg g(-1) of cellular dry weight. To our knowledge this is the first report of CYN in A. flos-aquae.


Asunto(s)
Aphanizomenon/aislamiento & purificación , Aphanizomenon/metabolismo , Agua Dulce/microbiología , Uracilo/análogos & derivados , Alcaloides , Toxinas Bacterianas , Toxinas de Cianobacterias , Alemania , Uracilo/biosíntesis
10.
PLoS One ; 10(11): e0142986, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26599484

RESUMEN

Non-pregnancy associated (N-PA) listeriosis, caused by Listeria monocytogenes, is a rare but severe disease, and is predominantly food-borne. Most cases appear sporadic and their infection vehicle remains unknown. Incidence has increased since 2008 in Germany. We aimed to identify underlying conditions and foods associated with sporadic N-PA listeriosis in Germany. We performed a nationwide case-control study from March 2012-December 2013. Cases were sporadic N-PA listeriosis patients notified to public health. Control subjects were age (40-65 years, 66-75 years, ≥ 76 years) frequency-matched persons from a nationwide random telephone sample. A structured questionnaire collected information on underlying diseases, therapies and >60 food items. We conducted multivariable logistic regression analysis, adjusting for host factors identified by causal diagram theory, and calculated population attributable fractions. We enrolled 109 cases and 1982 controls. Cases' median age was 69 years, 55% were male, 44% received immunosuppressive therapy within 3 months prior to illness onset; a further 28% had at least one immunocompromising disease. In multivariable analysis, immunosuppressive therapy (OR 8.8, 95%CI 4.9-15.6), immunocompromising disease (OR 2.7; 95%CI 1.4-5.2), gastric acid suppression (OR 3.0; 95%CI 1.4-6.3), the consumption of cold cooked sausages (OR 2.6; 95%CI 1.6-4.4), the preferred consumption of packaged cheese (OR 2.1; 95%CI 1.3-3.5) and pre-sliced cheese (OR 2.2; 95%CI 1.3-3.7) were significantly associated with N-PA listeriosis. These foods accounted for 59% of all cases. Typical high risk foods, e.g. cold seafood, certain types of cheeses, tended to be negatively associated with disease. In conclusion, immunosuppressive therapy and frequently consumed ready-to-eat foods are the main risk factors for sporadic N-PA listeriosis in Germany. To reduce their risk, immunocompromised persons should consume the identified foods well before the 'use-by' date. The microbiological criteria for Listeria monocytogenes in ready-to-eat foods may insufficiently protect persons who are markedly immunocompromised.


Asunto(s)
Comida Rápida/efectos adversos , Huésped Inmunocomprometido , Listeria monocytogenes/patogenicidad , Listeriosis/patología , Anciano , Comida Rápida/microbiología , Femenino , Alemania , Humanos , Listeriosis/etiología , Listeriosis/microbiología , Masculino , Persona de Mediana Edad , Embarazo , Factores de Riesgo
11.
Toxins (Basel) ; 6(10): 2932-47, 2014 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-25271784

RESUMEN

As the biosynthesis of cylindrospermopsin (CYN) is assumed to depend on nitrogen availability, this study investigated the impact of nitrogen availability on intra- and extracellular CYN and deoxy-CYN (D-CYN) contents in three Aphanizomenon strains from temperate waters. Nitrogen deficient (-N) cultures showed a prolonged growth phase and intracellular toxin accumulation by a factor of 2-6. In contrast, cultures with additional nitrate supply (+N) did not accumulate CYN within the cells. Instead, the maximum conceivable CYN release estimated for dead cells (identified by SYTOX Green staining) was much lower than the concentrations of dissolved CYN actually observed, suggesting these cultures actively release CYN from intact cells. Furthermore, we found remarkably altered proportions of CYN to D-CYN: as batch cultures grew, the proportion of D-CYN increased by up to 40% in +N medium, whereas D-CYN remained constant or decreased slightly in -N medium. Since +N cultures showed similar toxin patterns as -P cultures with increased extracellular CYNs and higher proportion of D-CYN we conclude that nitrogen limitation may affect the way the cells economize resources, especially the yield from phosphorus pools, and that this has an impact on CYN production and release. For water management, these result imply that nutrient availability not only determines the abundance of potentially CYN-producing cyanobacteria, but also the amount of extracellular CYNs (challenging drinking-water treatment) as well as the ratio of D-CYN to CYN (affecting toxicity).


Asunto(s)
Aphanizomenon/metabolismo , Nitrógeno/análisis , Uracilo/análogos & derivados , Alcaloides/biosíntesis , Aphanizomenon/clasificación , Toxinas Bacterianas , Medios de Cultivo/química , Toxinas de Cianobacterias , Agua Dulce/microbiología , Fósforo/análisis , Uracilo/biosíntesis
12.
PLoS One ; 8(11): e78180, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24244292

RESUMEN

The clinical spectrum following infection with Shiga toxin-producing Escherichia coli (STEC) is wide ranging and includes hemorrhagic colitis and life-threatening hemolytic uremic syndrome (HUS). Severity of STEC illness depends on patients' age and strongly on the infecting strains' virulence. Serogroup O157 is often assumed to be more virulent than others. Age-adjusted population-based data supporting this view are lacking thus far. We conducted a large retrospective cohort study among patients of community-acquired gastroenteritis or HUS diagnosed with STEC infection, reported in Germany January 2004 through December 2011. Age-adjusted risks for reported hospitalization and death, as proxies for disease severity, were estimated for STEC serogroups separately, and compared with STEC O157 (reference group) using Poisson regression models with robust error estimation. A total of 8,400 case-patients were included in the analysis; for 2,454 (29%) and 30 (0.4%) hospitalization and death was reported, respectively. Highest risks for hospitalization, adjusted for age and region of residence, were estimated for STEC O104 (68%; risk ratio [RR], 1.33; 95% confidence interval [CI], 1.19-1.45), followed by STEC O157 (46%). Hospitalization risks for the most prevalent non-O157 serogroups (O26, O103, O91, O145, O128, O111) were consistently and markedly lower than for O157, with the highest RR for O145 (0.54; 95% CI, 0.41-0.70) and the lowest for O103 (0.27; 95% CI, 0.20-0.35). Mortality risk of O104 was similar to O157 (1.2% each), but the group of all other non-O157 STEC had only 1/10 the risk (RR, 0.09; 95% CI, 0.02-0.32) compared to O157. The study provides population-based and age-adjusted evidence for the exceptional high virulence of STEC O157 in relation to non-O157 STEC other than O104. Timely diagnosis and surveillance of STEC infections should prioritize HUS-associated E. coli, of which STEC O157 is the most important serogroup.


Asunto(s)
Escherichia coli O157/patogenicidad , Síndrome Hemolítico-Urémico/microbiología , Síndrome Hemolítico-Urémico/mortalidad , Hospitalización , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Alemania/epidemiología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Especificidad de la Especie
13.
Environ Toxicol ; 22(1): 26-32, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17295278

RESUMEN

The frequent occurrence of the cyanobacterial toxin cylindrospermopsin (CYN) in the (sub)tropics has been largely associated with cyanobacteria of the order Nostocales of tropical origin, in particular Cylindrospermopsis raciborskii. C. raciborskii is currently observed to spread northwards into temperate climatic zones. In addition, further cyanobacteria of the order Nostocales typically inhabiting water bodies in temperate regions are being identified as CYN-producers. Therefore, data on the distribution of CYN in temperate regions are necessary for a first assessment of potential risks due to CYN in water used for drinking and recreation. A total of 127 lakes situated in the north-eastern part of Germany were investigated in 2004 for the presence of the toxin CYN and the phytoplankton composition. The toxin could be detected in half of the lakes (n = 63) and in half of 165 samples (n = 88). Concentrations reached up to 73.2 microg CYN/g DW. CYN thus proved more widely distributed than previously demonstrated. The analyses of phytoplankton data suggest Aphanizomenon sp. and Anabaena sp. as important CYN producers in Germany, and confirm recent findings of Aphanizomenon flos-aquae as CYN-producing species frequently inhabiting water bodies in temperate climatic regions. The data shown here suggest that CYN may be an important cyanobacterial toxin in German water bodies and that further data are needed to assess this.


Asunto(s)
Toxinas Bacterianas/aislamiento & purificación , Agua Dulce/microbiología , Toxinas Marinas/aislamiento & purificación , Microcistinas/aislamiento & purificación , Uracilo/análogos & derivados , Contaminantes del Agua/aislamiento & purificación , Contaminantes del Agua/toxicidad , Alcaloides , Anabaena/aislamiento & purificación , Anabaena/metabolismo , Aphanizomenon/aislamiento & purificación , Aphanizomenon/metabolismo , Toxinas Bacterianas/metabolismo , Clima , Toxinas de Cianobacterias , Monitoreo del Ambiente , Geografía , Alemania , Toxinas Marinas/metabolismo , Microcistinas/metabolismo , Medición de Riesgo , Uracilo/aislamiento & purificación , Uracilo/metabolismo , Contaminantes del Agua/metabolismo
14.
Bioorg Med Chem Lett ; 16(16): 4220-2, 2006 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-16777415

RESUMEN

The cyanobacterium Hassallia sp. produces a family of four compounds which exhibit a broad spectrum of antifungal activities. So far only one of these members has been isolated and its structure elucidated. In this study, we present a second member of this group. Mass spectrometry, one- and two-dimensional NMR and chiral GC-MS analysis revealed the same peptidic and fatty acid core for hassallidin B as the first member hassallidin A with an additional carbohydrate unit, a rhamnose attached to the 3-hydroxyl group of the C(14)-acyl side chain. The antifungal potential of hassallidin B is nearly identical to that of hassallidin A.


Asunto(s)
Antifúngicos/farmacología , Química Farmacéutica/métodos , Glucolípidos/química , Glicopéptidos/síntesis química , Glicopéptidos/farmacología , Lipoproteínas/química , Péptidos Cíclicos/síntesis química , Péptidos Cíclicos/farmacología , Cianobacterias/metabolismo , Diseño de Fármacos , Cromatografía de Gases y Espectrometría de Masas , Glucolípidos/farmacología , Lipopéptidos , Lipoproteínas/farmacología , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Modelos Químicos , Péptidos Cíclicos/química
15.
J Nat Prod ; 68(5): 695-700, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15921412

RESUMEN

Hassallidin A (1), a new antifungal glycosylated lipopeptide, was isolated from an epilithic cyanobacterium collected in Bellano, Italy, identified as Tolypothrix (basionym Hassallia) species. Chemical, mass spectrometric, and spectroscopic analyses, including one- and two-dimensional NMR, were performed to determine an esterified eight-residue cyclic peptide linked with a carbohydrate and a fatty acid residue. Chiral GC-MS analysis revealed the occurrence of the nonproteinogenic amino acids D-allo-Thr, D-Thr, D-Tyr, D-Gln, and dehydroaminobutyric acid (Dhb) within the peptide moiety. The additional components of hassallidin A could be identified as alpha,beta-dihydroxytetradecanoic acid (Dht) and mannose. This is the first report on a cyclic peptide of cyanobacterial origin that contains both a fatty acid and a carbohydrate moiety. Compound 1 exhibits antifungal activity against Aspergillus fumigatus and Candida albicans with MIC values of 4.8 microg/mL for both test organisms.


Asunto(s)
Alcaloides/aislamiento & purificación , Antifúngicos/aislamiento & purificación , Cianobacterias/química , Glucolípidos/aislamiento & purificación , Glicopéptidos/aislamiento & purificación , Lipoproteínas/aislamiento & purificación , Alcaloides/química , Alcaloides/farmacología , Secuencia de Aminoácidos , Antifúngicos/química , Antifúngicos/farmacología , Aspergillus fumigatus/efectos de los fármacos , Candida albicans/efectos de los fármacos , Glucolípidos/química , Glucolípidos/farmacología , Glicopéptidos/química , Glicopéptidos/farmacología , Italia , Lipopéptidos , Lipoproteínas/química , Lipoproteínas/farmacología , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular
16.
Microbiology (Reading) ; 150(Pt 6): 1785-1796, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15184565

RESUMEN

Microcystis sp. has been recognized in recent years as a producer of a high number of secondary metabolites. Among these, peptides that are produced by the non-ribosomal peptide synthetase pathway often show bioactivity or are toxic to humans. The production of particular peptides is specific for individual Microcystis clones, allowing their characterization as chemotypes by analysing the peptidome. The authors studied the in situ diversity of peptides and chemotypes in Microcystis communities from lakes in and around Berlin, Germany, by direct analysis of individual colonies by MALDI-TOF mass spectrometry. From 165 colonies analysed a total of 46 individual peptides could be identified, 21 of which have not been described previously. For six of the new peptides the structures could be elucidated from fragment patterns, while for others only a preliminary classification could be achieved. In most colonies, two to ten individual peptides were detected. In 19 colonies, 16 of which were identified as M. wesenbergii, no peptide metabolites could be detected. The peptide data of 146 colonies were subjected to an ordination (principal components analysis). The principal components were clearly formed by the microcystin variants Mcyst-LR, -RR and -YR, anabaenopeptins B and E/F, a putative microviridin, and a new cyanopeptolin. In the resulting ordination plots most colonies were grouped into five distinct groups, while 40 colonies scattered widely outside these groups. In some cases colonies from different lakes clustered closely, indicating the presence of similar chemotypes in the respective samples. With respect to colony morphology no clear correlation between a chemotype and a morphospecies could be established, but M. aeruginosa, for example, was found to produce predominantly microcystins. In contrast, M. ichthyoblabe colonies were mostly negative for microcystins and instead produced anabaenopeptins. The number of peptides detected in a limited number of samples and the various combinations of peptides in individual Microcystis colonies highlights the immense metabolic potential and diversity of this genus.


Asunto(s)
Microcystis/clasificación , Oligopéptidos/clasificación , Oligopéptidos/metabolismo , Péptidos Cíclicos/clasificación , Péptidos Cíclicos/metabolismo , Agua Dulce/microbiología , Alemania , Microcystis/citología , Microcystis/crecimiento & desarrollo , Microcystis/metabolismo , Oligopéptidos/química , Péptidos Cíclicos/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
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