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I Pfeiffer

Publications and source records attributed to I Pfeiffer.

At least 19 recordsLinked to original sources
PubMed2006

Application of bovine microsatellite markers for genetic diversity analysis of European bison (Bison bonasus).

In this study, the cross-amplification of a commercial multiplex set of 11 cattle (Bos taurus) microsatellites was tested on a panel of 35 European bison (Bison bonasus) individuals. After polymerase chain reaction optimization, all loci cross-amplified successfully in investigated bisons. Number of alleles and observed and expected heterozygosity per locus are in the range of 2-4, 0.086-0.629 and 0.288-0.621 respectively. The availability of a heterologous set of multiplexed microsatellite markers derived from cattle opens an avenue for collecting profound genetic data for efficient conservation management strategies of the European bison.

Animals↗
PubMed2006

Characterisation of the anticryptococcal effect of the FC-1 toxin produced by Filobasidium capsuligenum.

The basidiomycetous yeast Filobasidium capsuligenum produces a killer toxin (FC-1) which is highly effective against the opportunistic fungal pathogen Cryptococcus neoformans. The aim of this work was to study the effect of the toxin on C. neoformans cells. The sensitivities of strains representing eight molecular subtypes (VNI-IV and VGI-IV) of the C. neoformans species complex, and of an additional 50 clinical and environmental isolates were determined. Analysis of cellular DNA by laser scanning cytometry and fluorescein isothiocyanate (FITC) staining of the toxin-treated cells revealed that the killing mechanism of FC-1 is neither cell cycle- nor cell wall biosynthesis-dependent; rather it may act as an ionophoric protein that disrupts the cytoplasmic membrane function. The competition assay results suggest that beta-1,6-glucan in the cell wall may provide the binding site for the killer protein. This anticryptococcal toxin has the potential to be applied as a therapeutic agent for the treatment of cryptococcosis.

Animals↗
PubMed2005

Molecular phylogeny of selected predaceous leeches with reference to the evolution of body size and terrestrialism.

The phylogenetic relationships of erpobdellid leeches collected throughout Europe were investigated using newly obtained mitochondrial cytochrome c oxidase subunit I (CO-I) gene sequence data from 10 taxa. Monophyly of the five European Erpobdella species (sub-family Erpobdellinae) was supported, but a newly discovered leech, E. wuttkei Kutschera, 2004 (the smallest member of its genus, discovered in an aquarium) was only distantly related to this clade. Three members of the semiaquatic Trochetinae were included in this study. The largest European leech species discovered so far, Trocheta haskonis Grosser, 2000, was found to be a terrestrial predator that feeds on earthworms. The rare species T. haskonis is the sister taxon of T. bykowskii Gedroyc, 1913, a well-known amphibious leech. Based on a comparison of body sizes and a phylogenetic tree the evolution of terrestrialism in the family Erpobdellidae is discussed.

Aging↗
PubMed2005

X- and Y-chromosome specific variants of the amelogenin gene allow sex determination in sheep (Ovis aries) and European red deer (Cervus elaphus).

BACKGROUND: Simple and precise methods for sex determination in animals are a pre-requisite for a number of applications in animal production and forensics. However, some of the existing methods depend only on the detection of Y-chromosome specific sequences. Therefore, the abscence of a signal does not necessarily mean that the sample is of female origin, because experimental errors can also lead to negative results. Thus, the detection of Y- and X-chromosome specific sequences is advantageous. RESULTS: A novel method for sex identification in mammals (sheep, Ovis aries and European red deer, Cervus elaphus) is described, using a polymerase chain reaction (PCR) and sequencing of a part of the amelogenin gene. A partial sequence of the amelogenin gene of sheep and red deer was obtained, which exists on both X and Y chromosomes with a deletion region on the Y chromosome. With a specific pair of primers a DNA fragment of different length between the male and female mammal was amplified. CONCLUSION: PCR amplification using the amelogenin gene primers is useful in sex identification of samples from sheep and red deer and can be applied to DNA analysis of micro samples with small amounts of DNA such as hair roots as well as bones or embryo biopsies.

Amelogenin↗
PubMed2005

Frequency of the canine leucocyte adhesion deficiency (CLAD) mutation among Irish red setters in Germany.

Canine leucocyte adhesion deficiency (CLAD) is an autosomal recessive hereditary disease occurring among Irish red setters. The genetic defect causative for this disorder was recently identified as a missense mutation in the ITGB2 gene. Irish red setters with one copy of the mutant gene appear normal, while dogs with two copies of the mutant gene manifest the disease. The present report describes the analysis of the single nucleotide polymorphism in 289 Irish red setters by DNA sequencing. The frequency of CLAD carriers in Germany is 11%.

Animals↗
PubMed2004

Forensic DNA-typing of dog hair: DNA-extraction and PCR amplification.

The forensic application of DNA-typing for the identification of dog hair provides objective evidence in the characterisation of traces found at crime scenes. During the past few years forensic dog identity testing has been improved considerably using multiplex PCR systems. However, DNA-typing from samples of one up to 10 dog hairs is often problematic in forensic science. A single dog hair contains very small quantities of DNA or the hair sample consists of hairs with roots of bad quality or even of broken hairshafts without roots. Here we describe an experimental study about dog hairs by means of a Ca(2+) improved DNA-extraction method, quantification and amplification.

Animals↗
PubMed2004

The occurrence of an Australian leech species (genus Helobdella) in German freshwater habitats as revealed by mitochondrial DNA sequences.

The freshwater leech Helobdella europaea Kutschera 1987 was discovered twenty years ago in Germany and described as a new species. Here, we show that this leech is genetically identical with the Australian species Helobdella papillornata (CO-I-mt-DNA sequence identity of alignment positions: 98%). We conclude that H. europaea (syn. H. papillornata) represents an introduced annelid that occupies the same ecological niche as the common European leech H. stagnalis L.

Animals↗
PubMed2003

Analysis of the 5' region of the canine PAX3 gene and exclusion as a candidate for Dalmatian deafness.

The causative mutation in a gene related to hearing loss in Dalmatians has been elusive. Because of its role in melanocyte migration and differentiation as integral component of the inner ear, we hypothesized that the canine PAX3 (paired box homeotic gene 3) gene could be a candidate for Dalmatian deafness. Therefore, we isolated the canine PAX3 gene and searched for causative mutations within the coding region of important regulatory domains of PAX3. However, no mutations were identified when comparing the DNA sequences of healthy and affected dogs. These results were confirmed by a two-point linkage analysis in 203 Dalmatians transmitting deafness. Our data clearly show that the canine PAX3 gene can be excluded as candidate for Dalmatian deafness.

Animals↗
PubMed2001

Intron mobility results in rearrangement in mitochondrial DNAs of heterokaryon incompatible Aspergillus japonicus strains after protoplast fusion.

Mitochondrial transmission was carried out under selective conditions between incompatible Aspergillus japonicus strains always using an oligomycin-resistant mitochondrial donor and selecting for recipient nuclei and oligomycin-resistant mitochondria. All attempted intraspecific mitochondrial transmissions were successful, but the transmission between closely related A. japonicus and A. aculeatus failed. Under selection pressure, resistant progeny harbor the mitochondrial DNA (mtDNA) of the donor strain, which may remain unchanged or may be modified by the introns of the recipient mitochondrial genome. Detailed analysis of a certain strain harboring rearranged mtDNA suggests that the mtDNA profiles of recombinant-like progeny are strongly influenced by the characteristics and mobility of introns of both parental mtDNAs. Both intron loss and intron acquisition play a role in the rearrangement of mtDNA. In certain parental combinations, a particular intron was lost very frequently.

Aspergillus↗
PubMed2001

Genetic diversity in the red yeast Cryptococcus hungaricus and its phylogenetic relationship to some related basidiomycetous yeasts.

Cryptococcus hungaricus is a basidiomycetous yeast with the abilities to synthesize carotenoid pigments and to grow under psychrophile conditions. Six C. hungaricus strains have been isolated so far from different habitats. In this study we wished to clarify the relationships amongst them. Morphological and physiological characters, mitochondrial DNA restriction profiles, and the presence of mycoviruses were examined. Internal transcribed spacers together with the 5.8S rDNA, the D1/D2 region of 26S rDNA, and partial sequences of the 18S rRNA gene were also analysed. On the basis of the phylogenetic analyses the type strain CBS 4214(T) together with four other C. hungaricus isolates were closely related to Bullera armeniaca and Bullera crocea, while strain CBS 6569 was much more similar to Cystofilobasidium than to the other C. hungaricus isolates.

Basidiomycota↗
PubMed2001

Effects of double-stranded RNA viruses on the reproduction of Phaffia rhodozyma.

DsRNA viruses were transferred from a virus-containing strain to a virus-free strain of Phaffia rhodozyma by protoplast fusion. The resulting new strain carried all three types of dsRNA of the virus-containing strain and had the electrophoretic karyotype of the virus-free strain. The effects of the dsRNA viruses on the host fitness were checked by following the asexual and the sexual reproductivity. The results demonstrated that viruses have no effect on the growth rate during the lag and log phases of the vegetative reproduction, but the maximum cell numbers in the stationary phase differ significantly. Inconclusive results were obtained as concerns the effects of viruses on the sexual reproduction.

Basidiomycota↗
PubMed2000

Palaeogenetic analysis of (pre)historic artifacts and its significance for anthropology.

The possibility of isolating ancient DNA (aDNA) from all kinds of (pre)historic anthropogenetic artifacts opens new perspectives. This study applies palaeogenetic techniques to three anthropological issues: 1. Palaeodiet. DNA sequences from organic residues in vessels identify Precolumbian Aztec diet. 2. (Pre)historic husbandry and economic structures. aDNA data can reveal the species and the genetic evolutionary stage of animals and plants and show the manner and the extent of their growth, cultivation, or domestication. 3. Production techniques, use, and functionality. Identification of the plant or animal source of an archaeological find can reveal the use or the function of the find. Examples from a Celtic "sausage-end" and an Aztec "eye salve" are given.

Archaeology↗
PubMed1999

Interpretation of variability of mitochondrial genomes in the species Aspergillus carbonarius.

For interpretation of intraspecific polymorphism and the considerable differences in the size of mtDNAs among three groups of A. carbonarius, restriction maps were constructed from several enzymes. Functional maps were also developed to compare genome organisations and gene content. The appearance of various mtDNAs of A. carbonarius strains are different in size, but their gene content is almost identical. The 1.1 kb size difference between two closely related subgroups (1a, 1b) can be attributed to the presence or absence of an intron in cox2 gene. This phenomenon demonstrates that the migration of introns is possibly responsible for the development of variable mitochondrial genomes in nature. The striking differences in size and restriction patterns between two main mtDNA groups might derive from both the intronal variations and the altered intergenic organisation.

Aspergillus↗