Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 25
Filter
1.
Allergol Select ; 2(1): 10-16, 2018.
Article in English | MEDLINE | ID: mdl-31826039

ABSTRACT

Allergic skin and respiratory diseases range among the most frequent afflictions in industrialized countries. Due to this fact the importance of indoor mold pollution based on dampness is discussed. In a sentinel health study of the State Health Agency (LGA) children attending of 4th grade of a primary school were tested by an in-vitro allergy screening (UniCap 100/Phadia) for the mold allergens mx1 (Penicillium chrysogenum m1, Cladosporium herbarum m2, Aspergillus fumigatus m3 and Alternaria alternata m6). Primarily about 5% of the children were sensitized against molds which are associated with the ambient air. The investigations showed that most of the children were sensitized against Alternaria alternata and concerning the IgE-concentration (kU/l) Alternaria alternata had the highest concentration among the tested allergens. Commonly children with sensitization against molds were polysensitized. It is unclear if the allergy screening against mold mx1 includes molds with indication for indoor mold pollution such as Acremonium spp., Aspergillus penicillioides, Aspergillus restrictus, Aspergillus versicolor, Chaetomium spp., Phialophora spp., Stachybotrys chartarum, Tritirachium (Engyodontium) album und Trichoderma spp. by means of crossreaction. Therefore, such investigations do not admit any conclusion about health problems as a result of indoor mold pollution. At the present state of knowledge exposure measurements of indoor mold pollutions are not possible, at most a semiquantitative assessment. Although it is generally accepted that dwellings with moisture and mold represent a health risk, knowledge about indoor mold pollution and the related health problems is lacking.

2.
Dtsch Med Wochenschr ; 138(33): 1651-8, 2013 Aug.
Article in German | MEDLINE | ID: mdl-23913351

ABSTRACT

BACKGROUND AND OBJECTIVE: Allergic diseases of the respiratory tract are common atopic diseases in the population. Pollen of plants are one of their main causes. Pollen of trees, grasses, and weeds like mugwort are of particular importance in this context. The purpose of the present study was to determine the association between typical respiratory symptoms due to pollen allergens and the sensitization to pollen of ragweed and mugwort in adults. METHODS: 1039 participants (18 to 66 years) from Southwest Germany were included in this cross-sectional study. Complains typically for aeroallergens were recorded by questionnaire. In-vitro existing sensitizations were determined for grasses/early bloomer (gx1), trees (tx6), mugwort (w6 and Art-v1) and ragweed (w1 and Amb-a1) by testing for specific IgE-antibodies. RESULTS: In a screening test with a mixed allergen sample (sx1) 36.0 % of the participants showed an aeroallergen sensitization. Consecutive investigations of these 374 positive samples revealed a sensitization to grasses/early bloomer, trees, ragweed (w1), mugwort (w6) and the major allergens ragweed (Amb-a1) and mugwort (Art-v1) in 61.8 %, 54.5 %, 29.9 %, 24.3 %, 1.9 %, and 12.3 %, respectively. This corresponds to 22.2 %, 19.6 %, 10.8 %, 8.7 %, 0.7 % and 4.4 %, respectively, in the whole study population. The participants tested positively stated significantly more disorders. On average, 51.1 % had known hay fever, 65.2 % sneezing without cold and 41.5 % sneezing due to contact with grasses or flowers. In contrast, participants tested negatively stated disorders in only 4.4 %, 32.5 %, and 3.9 %, respectively. CONCLUSION: In Southwest Germany, sensitizations to plant pollen mainly are still caused by grasses, trees, and weeds like mugwort. A sensitization to pollen of ragweed alone is rare until now. However, in case of continuous allergic disorders of the respiratory tract in late summer, a sensitization to ragweed can be important for differential diagnostics.


Subject(s)
Artemisia/immunology , Hypersensitivity, Immediate/epidemiology , Hypersensitivity, Immediate/immunology , Respiratory Hypersensitivity/epidemiology , Respiratory Hypersensitivity/immunology , Rhinitis, Allergic, Seasonal/epidemiology , Rhinitis, Allergic, Seasonal/immunology , Adolescent , Adult , Aged , Ambrosia/immunology , Comorbidity , Female , Germany/epidemiology , Humans , Incidence , Male , Middle Aged , Particulate Matter/immunology , Risk Assessment , Young Adult
3.
Dtsch Med Wochenschr ; 134(28-29): 1457-63, 2009 Jul.
Article in German | MEDLINE | ID: mdl-19572244

ABSTRACT

BACKGROUND AND OBJECTIVE: Allergic skin and respiratory diseases show a high prevalence in most industrial countries. In addition, during the last years ragweed colonization has increased in Europe. Ambrosia pollen ( AMBROSIA ARTEMISIIFOLIA L. - common ragweed) are highly allergenic. Due to the late flowering time (august/September) of ragweed this can result in increasing health threats for allergic populations. This is of particular importance for those who already are sensitive to some grass or tree pollen. These individuals can then suffer from allergies during nearly the whole year. The present study examined the prevalence of sensitization to ragweed in German children and possible health implications. METHODS: Between 2004 and 2007 sera of 1323 10-years old children in Baden Württemberg were tested in-vitro for specific IgE-antibodies against common aeroallergens including ragweed pollen. RESULTS: Specific IgE-antibodies to extracts of common ragweed pollen were present in 10 - 17 % of the tested sera depending on the year of investigation. CONCLUSION: The determined specific IgE-antibodies may be the result of a direct sensitization to ragweed pollen or correspond to cross-reactivity to other plants of the asteraceae subfamily or some nutritional allergens. The detection of sensitization to ragweed pollen does not prove actual allergic disease. However, a ragweed derived allergy should be considered in the differential diagnosis when allergic symptoms are present in direct connection to the flowering-time of ragweed. Ragweed plants should be removed and the spread of the plant 'restricted', as experiences in other countries with already wide spreading show.


Subject(s)
Allergens/adverse effects , Ambrosia/adverse effects , Pollen/adverse effects , Rhinitis, Allergic, Seasonal/etiology , Allergens/immunology , Ambrosia/immunology , Child , Female , Germany/epidemiology , Humans , Immunoglobulin E/blood , Male , Pollen/immunology , Prevalence , Rhinitis, Allergic, Seasonal/epidemiology
4.
Gesundheitswesen ; 67(4): 302-11, 2005 Apr.
Article in German | MEDLINE | ID: mdl-15856391

ABSTRACT

Although PCB and PCB-containing materials are not processed for a long time, PCB is under discussion again and again caused by the pollution of indoor environments. To objectify the discussion, the dates of the PCB-biomonitoring, the organochlorine-compounds (DDE, HCB, beta-/gamma -HCH, PCDD/PCDF) and the polybrominated biphenyl ethers concerning the investigations within the project "Sentinel Health Departments" in Baden-Wurttemberg are represented. Additionally results from children from Kazakhstan (Aral-Sea area) and from teachers which are working in PCB polluted schools as well as from a long term investigated test person are reported. Blood concentrations of the following compounds decreased from 1996/97 to 2002/03: the sum of the concentration of PCB 138,153 and 180 decreased from 0.46 microg/L to 0.20 microg/L, DDE from 0.32 microg/L to 0.17 microg/, HCB from 0.20 microg/L to 0.08 microg/L, beta-HCH below the level of detection, I-TEQ NATO to 4.8 pg/g blood fat, TEQ WHO (without PCB) to 5.5 pg/g blood fat, PCB 126 to 18,8,pg/g blood fat and PCB 169 to 12.8 pg/g blood fat. The influence of breast feeding and the gender on the level of the pollution is conspicious. No local correlations were found in Baden-Wurttemberg, but they were found in comparison with the results of Kazakhstan (Aral-Sea area). The difficulty to produce time series while the analyzing pollutants are more and more decreasing, as well as the change of the calculation base of the summation of parameters like I-TEQ NATO to TEQ WHO are discussed.


Subject(s)
Biphenyl Compounds/blood , Environmental Monitoring , Environmental Pollutants/blood , Hydrocarbons, Chlorinated/blood , Pesticides/blood , Polychlorinated Dibenzodioxins/analogs & derivatives , Adult , Age Factors , Benzofurans/blood , Body Burden , Breast Feeding , Child , Child, Preschool , Chromatography, Gas , Data Interpretation, Statistical , Dichlorodiphenyl Dichloroethylene/blood , Female , Fungicides, Industrial/blood , Germany , Hexachlorobenzene/blood , Humans , Insecticides/blood , Kazakhstan , Male , Polybrominated Biphenyls/blood , Polychlorinated Biphenyls/blood , Polychlorinated Dibenzodioxins/blood , Sex Factors , Soil Pollutants/blood
5.
Article in German | MEDLINE | ID: mdl-15650901

ABSTRACT

The assessment of mold concentrations in air samples requires generally accepted evaluation criteria. It is not possible to derive guideline values based on risk assessment. Background concentrations are therefore used as the basis for the assessment of measured concentrations. The assessment criteria established by the Federal Environmental Agency in Berlin and by the State Health Agency of Baden-Wurttemberg are founded on the experience of some laboratories. The general application of these criteria is only meaningful if validated and generally applied methods of analysis are used. Until now, laboratories have been using many different methods for sampling and detection of culturable molds and total spore counts in air. In this study, different steps for sampling by impaction or filtration are validated. The results presented will contribute to standardization of sampling and detection of molds in air.


Subject(s)
Air Pollutants/analysis , Air Pollution, Indoor/analysis , Fungi/growth & development , Microbiological Techniques/methods , Air Pollutants/adverse effects , Air Pollution, Indoor/adverse effects , Colony Count, Microbial , Fungi/classification , Fungi/pathogenicity , Germany , Humans , Reference Values , Risk Assessment
6.
Article in German | MEDLINE | ID: mdl-15650902

ABSTRACT

The mold concentration of indoor air and outdoor air in three parts of Germany was investigated in both winter and summer. In total, air samples from 80 dwellings, reportedly free from mold infestations, were analysed with both the cultivation method and the total spore count method. With the cultivation method, 40 mold species and genera were differentiated, while with the total spore count method, 11 spore types were distinguished. The concentration of the genera Alternaria, Cladosporium, Fusarium and yeast increased in summertime. In contrast, the concentrations of Aspergillus and Penicillium measured in summer were nearly equal to those measured in winter. The majority of the various molds were only found in a small number of samples, too small for a reliable comparison of the winter and summer findings. The 95th percentile of the indoor mold concentrations is suggested as the upper limit of the background concentration. The results are discussed comparing the assessment proposals of various authors, and a new assessment proposal is described.


Subject(s)
Air Pollution, Indoor/analysis , Fungi/isolation & purification , Microbiological Techniques , Air Pollution, Indoor/prevention & control , Colony Count, Microbial , Fungi/classification , Fungi/growth & development , Humans , Reference Values , Seasons , Topography, Medical
7.
Article in German | MEDLINE | ID: mdl-15650903

ABSTRACT

Examination of dust samples is widely used to detect sources of mold growth in indoor environments. The advantage of this investigation is that house dust can be regarded as a passive sampler collecting mold spores over a long time period. No generally accepted method exists, however, for sampling and analysis of house dust for the detection of molds. Therefore, results obtained by different laboratories are not comparable. Measurements with standardized validated methods are a prerequisite to assess concentrations of molds in indoor environments. The method presented is based on sampling with a modified filter holder (in accordance with VDI 4300 page 8). Mini-sieves of different sizes are used for sample preparation. The fraction <63 microm is used for cultivation of molds after suspension. Problems of dust sampling and preparation are discussed. Criteria for the detection of sources of mold growth based on dust samples are presented elsewere.


Subject(s)
Air Pollutants, Occupational/analysis , Air Pollution, Indoor/analysis , Dust/analysis , Fungi/isolation & purification , Colony Count, Microbial , Filtration/instrumentation , Fungi/classification , Fungi/growth & development , Humans , Microbiological Techniques/instrumentation
8.
Article in German | MEDLINE | ID: mdl-15650904

ABSTRACT

Mold concentrations of house dust samples from dwellings reportedly free from mold infestations were analysed to obtain background values. Samples from carpet floors were taken from 80 dwellings in three parts of Germany in winter and summer. Samples were analysed with the cultivation method (using suspension). This resulted in the detection of 35 mold species or genera. Concentrations of the genera Alternaria, Cladosporium, Fusarium and yeast increased in summer. In contrast concentrations of Aspergillus and Penicillium in the summer samples were nearly equal to those in the winter samples. The majority of the various molds were only found in a number of samples too small for a reliable comparison of the winter and summer findings to be made. The results were compared with findings of other authors. The authors propose the concentrations of the 95th percentile of each species (when representing over 10,000 KBE/g of dust) as background values, while a threefold higher value is regarded as an indication of mold presence. An exception should be made for the concentrations of molds which increase sharply in the outdoor air in summer. Because of the difficulty in estimating the outdoor influence, no evaluation proposals can be given for these species for the summer season.


Subject(s)
Air Pollution, Indoor/analysis , Dust/analysis , Fungi/isolation & purification , Colony Count, Microbial , Filtration/instrumentation , Floors and Floorcoverings , Fungi/classification , Fungi/growth & development , Germany , Humans , Microbiological Techniques/instrumentation , Reference Values , Seasons , Topography, Medical
9.
Article in German | MEDLINE | ID: mdl-15650905

ABSTRACT

In co-ordination with the Umweltbundesamt Berlin, the Landesgesundheitsamt Baden-Wurttemberg (LGA) initiated external quality assurance in the diagnosis of indoor fungi in autumn 2001. Four of six fungal strains commonly found indoors have to be fully identified (on the genus and species level). There are two distributions per year; the six distributions hitherto carried out resulted in correct identification by 46-89% of laboratories (40-71 participants, total 148). It is clear from the results that repeat participants were more successful. In addition to the pure cultures sent out we offered actual samples (two air samples, one wood material, one sample of house dust, hitherto); 43- 69% of participating laboratories also took part in this facultative investigation of actual samples and 29-62% were successful. Results that differed considerably revealed problems while treating and evaluating actual samples. Therefore, activities in this field should be enhanced. In conclusion, external quality assurance in the diagnosis of indoor fungi is a useful management aid in the maintenance and improvement of laboratory performance.


Subject(s)
Air Pollution, Indoor/analysis , Fungi/isolation & purification , Microbiological Techniques/standards , Colony Count, Microbial , Dust/analysis , Filtration/instrumentation , Fungi/classification , Fungi/growth & development , Humans , Quality Assurance, Health Care/standards , Reference Values , Sensitivity and Specificity
10.
Gesundheitswesen ; 66(8-9): 528-35, 2004.
Article in German | MEDLINE | ID: mdl-15372355

ABSTRACT

So far there have been rather few reliable and comparable data available on indoor pollution with mould. Following the publication of the Federal Environmental Agency and the Health Agency Baden-Württemberg which supports the assessment of mould pollution of indoor air, it seemed advisable to investigate as to how far these criteria can be used for the assessing the mould pollution in daily practice. The results of investigations of 130 homes and 117 classrooms in Baden-Württemberg. will be represented.


Subject(s)
Air Pollution, Indoor/analysis , Air Pollution, Indoor/statistics & numerical data , Environmental Monitoring/methods , Fungi/isolation & purification , Residence Characteristics/statistics & numerical data , Risk Assessment/methods , Schools/statistics & numerical data , Cities/epidemiology , Epidemiological Monitoring , Germany/epidemiology , Risk Factors , Spores, Fungal/isolation & purification
11.
Gesundheitswesen ; 65(7): 457-63, 2003 Jul.
Article in German | MEDLINE | ID: mdl-12891478

ABSTRACT

The study examined the exposure to biological indoor air agents and their possible role for allergies and respiratory tract illnesses of children. It was conducted as a case control study (atopic vs non-atopic children) at the four surveillance public health departments in Baden-Württemberg in the winter season 1999/2000 and included 379 children of the fourth class. The concentrations of the house dust mite antigens Der F1, Der p1, and Der Gr2 as well as cat allergen Fel d1 were determined in the children's bedrooms on the ground and in the mattress. Specific IgE-antibodies against allergens from house dust, mites and cat were determined in the serum of the children. For mite allergens the following medians ( micro g/g) were estimated in floor dust: Der p1 = 0.6, Der f1 = 2.3, Gr2 = 0.1; in mattresses: Der p1 = 1.2, Der f1 = 3.4, Gr2 = 0.3. The median of Fel d1 in floor dust was 0.2 microg/g, in mattresses 0.1 microg/g. Sensitisation to dust mite allergen was found to be more prevalent than sensitisation to cat. The distribution of sensitisation among the cases and controls is different. Among the cases, more subjects were sensitised to dust mites (32.9 %) and cat (13.1 %). Among the controls, 17.1 % were sensitised to dust mites and 4.1 % to cat. The results showed no direct association between the prevalence of allergies or respiratory tract illnesses and the indoor concentrations of the allergens. Possible reasons for these findings are discussed.


Subject(s)
Allergens , Cats/immunology , Dermatitis, Atopic/diagnosis , Mites/immunology , Respiratory Hypersensitivity/diagnosis , Allergens/analysis , Allergens/immunology , Animals , Bedding and Linens , Case-Control Studies , Child , Data Interpretation, Statistical , Dermatitis, Atopic/etiology , Dermatitis, Atopic/immunology , Dust/immunology , Enzyme-Linked Immunosorbent Assay , Germany , Humans , Respiratory Hypersensitivity/etiology , Respiratory Hypersensitivity/immunology , Surveys and Questionnaires
12.
Gesundheitswesen ; 65(5): 327-35, 2003 May.
Article in German | MEDLINE | ID: mdl-12772075

ABSTRACT

Since 1992, in Baden-Württemberg, ten-year old children have been surveyed in the project "Sentinel Health Departments" to study their exposure to environmental pollutants and possible health effects. In the four study areas 1200 children have been investigated every year initially, since 1996 every second year. The data for mercury in body fluids are reported here. The decrease in the body burden of mercury as a result of the declining usage of dental amalgam fillings, was been verified. In 1992/93, of all the children who had been surveyed, the 95 percentile for the body burden of mercury was 3.1 microg/l and in 2000/01 1.35 microg/l. Also to be discussed is the reason why mercury-based cosmetic ointments seriously exceed the HBM-II-intervention-value. Because of using these ointments, concentrations of mercury in urine up to 1400 microg/l were found. A study within the project "Sentinel Health Departments" compared the concentrations of mercury in the urine of adults with those in blood and salvia. The results support the opinion that mercury in urine is appropriate for estimating the mercury uptake from dental amalgam fillings. It can be assumed that these results reflect the situation in the entire Federal Republic of Germany. The ten years' experience confirms that the concept of the "Sentinel Health Departments" is excellently suited to obtain data relevant for environmental health of children. Environmental health protection and the essential gathering of data for future health observation in Baden-Württemberg.


Subject(s)
Dental Amalgam/adverse effects , Environmental Monitoring/statistics & numerical data , Environmental Pollutants/pharmacokinetics , Mercury Poisoning/epidemiology , Mercury/pharmacokinetics , Public Health/statistics & numerical data , Adult , Body Burden , Child , Environmental Pollutants/toxicity , Epidemiological Monitoring , Female , Germany/epidemiology , Humans , Male , Mercury/toxicity , Mercury Poisoning/diagnosis , Mercury Poisoning/prevention & control , Risk Factors , Saliva/metabolism , Sentinel Surveillance
13.
Gesundheitswesen ; 64(11): 602-7, 2002 Nov.
Article in German | MEDLINE | ID: mdl-12442220

ABSTRACT

BACKGROUND: In Germany, where geogenic selenium concentrations are low, only few data on selenium status in children are available. Aim of the study was to investigate serum selenium concentrations of children in a population-based sample and to additionally investigate spatial and temporal differences. METHOD: In three consecutive cross sectional studies the selenium concentration in serum was determined in 1,918 children (mean age 10.3 years) from four study areas. Potential factors of influence were assessed by questionnaires filled in by parents and physicians, respectively. Selenium determination was done by hydride atomic absorption spectrometry after microwave digestion. RESULTS: Mean selenium concentrations for the subcollectives ranged from 54.5 +/- 10.5 micro g/l to 71.9 +/- 15.1 micro g/l. The minimum observed was 14 micro g/l, the maximum 216 micro g/l. Turkish children had lower selenium concentrations than German children and children of other nationality, respectively. Controlling for sex and year of investigation German children from Stuttgart had significantly lower selenium concentrations than children from Aulendorf/Bad Waldsee. In the same regression model for the period from 1995/96 to 1998/99 a decreasing trend was found to be significant. However, the regression model only explains a very small part of variance. CONCLUSIONS: The selenium concentrations determined in this study are in the range also found in other studies in children from Germany. They are far below the toxicologically relevant range, which starts at about 600 micro g/l. The 5 th percentile in nearly all subcollectives was below the threshold limit of the lower tolerable selenium concentration of 45 micro g/l. For children from south Germany deficiency of selenium is therefore more to be suspected than a burden relevant to health. Selenium supplementation should however be considered thoroughly. Balanced nutrition is also a main factor for an optimum selenial supply.


Subject(s)
Health Status Indicators , Selenium/blood , Child , Cross-Sectional Studies , Female , Germany , Humans , Male , Reference Values , Regression Analysis , Selenium/deficiency
14.
Gesundheitswesen ; 63(11): 717-23, 2001 Nov.
Article in German | MEDLINE | ID: mdl-11713704

ABSTRACT

Abstract. In connection with the implementation of the study "Sentinel Health Departments" which was performed in 1992 in Baden-Württemberg by the Landesgesundheitsamt (LGA) the importance of Analytical Quality Protection (AQP) in the environmental medicine was emphasized. In 1994 the LGA established a quality circle in Baden-Württemberg (BW) in the area of the human biomonitoring. In 1998 the area of responsibilitiy was expanding and the quality circle was occupied with the "Biological Indoor Pollution" and the "Chemical Indoor Pollution" as well. In 2000 a group of members of the Sozialministerium BW, the Landesärztekammer BW and the four Kassenärztliche Vereinigungen of Baden-Württemberg was set up at the LGA. In 2001 the working group "Länderarbeitsgruppe umweltbezogener Gesundheitsschutz" (LAUG) intends to establish a project team which is called "Certification in the realm of the Human Biomonitoring". The coordination will be effected by the LGA. Until now the work of the qualitiy circle led to an improvement of the comparability of the results of the different laboratories and to a more realistic assessment of the uncertainty of the results referring to the environmental medical examinations.


Subject(s)
Environmental Medicine/legislation & jurisprudence , Management Quality Circles/legislation & jurisprudence , Quality Assurance, Health Care/legislation & jurisprudence , Air Pollution, Indoor/legislation & jurisprudence , Environmental Monitoring/legislation & jurisprudence , Germany , Humans , Risk Assessment
15.
Gesundheitswesen ; 63(6): 404-11, 2001 Jun.
Article in German | MEDLINE | ID: mdl-11467224

ABSTRACT

Elevated levels of moulds in homes may represent a risk for development of allergies and respiratory diseases. Little is known about the levels of these biogenic contaminants in homes in South-West Germany. This paper presents the results of a study which was performed between November 1997 and May 1998 in the four Sentinel Health Departments in Baden-Württemberg (Stuttgart, Mannheim, Kehl and Aulendorf/Bad Waldsee). It included 377 households in which children of 10 years of age resided. Moulds were determined in indoor air, outdoor air, household dust from floors and mattresses. Specific home characteristics were assessed by questionnaire. The median value of the number of colony forming units (CFU) in indoor air was 135 CFU/m3 (range 5-17,000) and in outdoor air 145 CFU/m3 (range 15-2,900). The median value of CFU/g dust, collected from the floors, was 15,000 (range 0-700,000) and collected from mattresses was 28,000 (range 1,500-1,350,000). The data suggest that an indoor-outdoor difference exceeding the value of 500 CFU/m3 indicates an elevated mould concentration in indoor air compared to background. This value can be discussed as a temporary reference value for South-West Germany in the winter season. However, a health assessment can not be derived from this value.


Subject(s)
Air Microbiology , Air Pollution, Indoor/statistics & numerical data , Fungi , Child , Dust/analysis , Female , Germany , Humans , Male
16.
Mol Microbiol ; 16(3): 521-34, 1995 May.
Article in English | MEDLINE | ID: mdl-7565112

ABSTRACT

The promoter region and transcriptional regulation of the nuoA-N gene locus encoding the proton-translocating NADH:quinone oxidoreductase was analysed. A 560 bp intergenic region upstream of the nuo locus was followed by a gene (designated lrhA for LysR homologue A) coding for a gene regulator similar to those of the LysR family. Disruption of lrhA did not affect growth (respiratory or non-respiratory) or expression of nuo significantly. Transcriptional regulation of nuo by electron acceptors, electron donors and the transcriptional regulators ArcA, FNR, NarL and NarP, and by IHF (integration host factor) was studied with protein and operon fusions containing the promoter region up to base pair -277 ('nuo277') or up to base pair -89 ('nuo899'). The expression of the nuo277-lacZ fusions was subject to ArcA-mediated anaerobic repression and NarL(+ nitrate)-mediated anaerobic activation. FNR and IHF acted as weak repressors under anaerobic conditions. Expression of nuo899-lacZ was stimulated during anaerobic fumarate respiration and aerobically by C4 dicarboxylates. Therefore, expression of nuo is regulated by O2 and nitrate via ArcA, NarL, FNR and IHF at sites within the -277 region, and by other factors including C4 dicarboxylates at a site between -277 and -899. A physiological role for the transcriptional stimulation by O2 and nitrate is suggested.


Subject(s)
Bacterial Proteins/genetics , Escherichia coli Proteins , Escherichia coli/genetics , Gene Expression Regulation, Bacterial , Iron-Sulfur Proteins , NADH Dehydrogenase/genetics , Protons , Repressor Proteins , Transcription Factors/genetics , Transcription, Genetic , Aerobiosis , Amino Acid Sequence , Bacterial Outer Membrane Proteins/physiology , Bacterial Proteins/physiology , Base Sequence , DNA-Binding Proteins/physiology , Electron Transport , Escherichia coli/growth & development , Integration Host Factors , Molecular Sequence Data , Operon , Promoter Regions, Genetic , Sequence Alignment , Sequence Homology, Amino Acid , Transcription Factors/physiology
18.
J Mol Biol ; 233(1): 109-22, 1993 Sep 05.
Article in English | MEDLINE | ID: mdl-7690854

ABSTRACT

The gene locus nuo of the proton-translocating NADH: ubiquinone oxidoreductase in Escherichia coli was identified by means of a DNA probe made by the polymerase chain reaction. The primers used for the reaction were derived from consensus sequences of the NAD(H)-binding subunit of mitochondrial NADH: ubiquinone oxidoreductase and the NAD(+)-reducing hydrogenase of Alcaligenes eutrophus. The nuo locus lies between minutes 49.2 and 49.6 on the E. coli chromosome and contains a cluster of 14 genes. They are bordered upstream by a sequence resembling sigma 70-dependent promoters and downstream by a sequence resembling rho-independent terminators. All 14 proteins derived from the nuo-genes are related to subunits of mitochondrial NADH: ubiquinone oxidoreductase, among which all subunits presumed to bind the substrates and to harbour the redox groups are found, as well as all seven mitochondrially encoded subunits. The E. coli enzyme seems to represent the minimal form of a proton-translocating NADH: ubiquinone oxidoreductase. The gene order in the nuo locus is conserved in comparison with other bacterial genomes and the chloroplast genome of higher plants. To some extent, the gene order correlates with the topological arrangement of the encoded subunits. The conception of modular evolution of NADH: ubiquinone oxidoreductase is further supported by the arrangement of the nuo-genes.


Subject(s)
Escherichia coli/genetics , Genes, Bacterial/genetics , NAD(P)H Dehydrogenase (Quinone)/genetics , Alcaligenes/genetics , Amino Acid Sequence , Base Sequence , Chromosome Mapping , DNA, Recombinant , Escherichia coli/enzymology , Formate Dehydrogenases/genetics , Gene Library , Hydrogenase/genetics , Mitochondria/enzymology , Molecular Sequence Data , Multienzyme Complexes/genetics , Polymerase Chain Reaction , Pseudomonas/enzymology , RNA/genetics , Regulatory Sequences, Nucleic Acid/genetics , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Transcription, Genetic
19.
J Bioenerg Biomembr ; 25(4): 331-7, 1993 Aug.
Article in English | MEDLINE | ID: mdl-8226714

ABSTRACT

The NADH:ubiquinone oxidoreductase (complex I) is made up of a peripheral part and a membrane part. The two parts are arranged perpendicular to each other and give the complex an unusual L-shaped structure. The peripheral part protrudes into the matrix space and constitutes the proximal segment of the electron pathway with the NADH-binding site, the FMN and at least three iron-sulfur clusters. The membrane part constitutes the distal segment of the electron pathway with at least one iron-sulfur cluster and the ubiquinone-binding site. Both parts are assembled separately and relationships of the major structural modules of the two parts with different bacterial enzymes suggest, that both parts also emerged independently in evolution. This assumption is further supported by the conserved order of bacterial complex I genes, which correlates with the topological arrangement of the corresponding subunits in the two parts of complex I.


Subject(s)
NAD(P)H Dehydrogenase (Quinone)/chemistry , Protein Conformation , Animals , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Biological Evolution , Cattle , Electron Transport , Escherichia coli/enzymology , Escherichia coli/genetics , Fungal Proteins/chemistry , Fungal Proteins/isolation & purification , Fungal Proteins/ultrastructure , Genes, Bacterial , Microscopy, Electron , Mitochondria, Heart/enzymology , NAD(P)H Dehydrogenase (Quinone)/genetics , NAD(P)H Dehydrogenase (Quinone)/isolation & purification , NAD(P)H Dehydrogenase (Quinone)/ultrastructure , Paracoccus denitrificans/enzymology , Paracoccus denitrificans/genetics , Protein Folding
SELECTION OF CITATIONS
SEARCH DETAIL