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K Pohlmeyer

Publications and source records attributed to K Pohlmeyer.

At least 19 recordsLinked to original sources
PubMed2005

A multivalent HIV-vaccine: development of a plasmid DNA for the expression of HIV envelope glycoproteins with hypervariable V3-loop domains.

The third hypervariable (V3) loop of the HIV-1 envelope glycoprotein gp120 plays an essential role in the process of viral entry. It contributes to the tropism, coreceptor usage and immune-escape of the virus. We generated a monovalent plasmid DNA and demonstrated the expression of HIV-1 clade B subtype NL4-3 gp120 and gp160 in comparison to a multivalent plasmid DNA encoding for a variety of V3-variants. In contrast to the membrane-anchored gp160, preliminary data demonstrate the monovariant gp120 is expressed in and presented on a human dendritic cell (DC) line, due to a HIVenv-specific re-stimulation of naïve T-cells detected by IFNgamma-ELISPOT assay.

AIDS Vaccines↗
PubMed2000

Identification of the pore-forming region of the outer chloroplast envelope protein OEP16.

The chloroplast outer envelope protein OEP16 forms a cation-selective high conductance channel with permeability to amines and amino acids. The region of OEP16 directly involved in channel formation has been identified by electrophysiological analysis of a selection of reconstituted OEP16 mutants. Because analysis of these mutants depended on the use of recombinant protein, we evaluated the electrophysiological properties of OEP16 isolated directly from pea chloroplasts and of the recombinant protein produced in Escherichia coli. The results show that the basic properties like conductance, selectivity, and open probability of the channel formed by native pea OEP16 are comparable with the channel activity formed by the recombinant source of the protein. Following electrophysiological analysis of OEP16 mutants we found that point mutations and insertion of additional amino acid residues in the region of the putative helix 1 (Glu(73) to Val(91)) did not change the properties of the OEP16 channel. The only exception was a Cys(71)-->Ser mutation, which led to a loss of the CuCl(2) sensitivity of the channel. Analysis of N- and C-terminal deletion mutants of OEP16 and mutants containing defined shuffled domains indicated that the minimal continuous region of OEP16, which is able to form a channel in liposomes, lies in the first half of the protein between amino acid residues 21 and 93.

Amines↗
PubMed1999

[Wild animals as transmitters of infectious diseases].

The present contribution contains a summarized overview of current literature dealing with the most important zoonoses that can be transmitted directly or indirectly from indigenous wildlife to man. Following Weber (1994) the diseases are classified according to the species of pathogen. Ways of infection are shown and the importance of these zoonoses is discussed with regard to the frequency of occurrence, the degree of sickness and the risk for man.

Animals↗
PubMed1998

A high-conductance solute channel in the chloroplastic outer envelope from Pea.

The pea chloroplastic outer envelope protein OEP24 can function as a general solute channel. OEP24 is present in chloroplasts, etioplasts, and non-green root plastids. The heterologously expressed protein forms a voltage-dependent, high-conductance (Lambda = 1.3 nS in 1 M KCl), and slightly cation-selective ion channel in reconstituted proteoliposomes. The highest open probability (P open approximately 0. 8) is at 0 mV, which is consistent with the absence of a transmembrane potential across the chloroplastic outer envelope. The OEP24 channels allow the flux of triosephosphate, dicarboxylic acids, positively or negatively charged amino acids, sugars, ATP, and Pi. Structure prediction algorithms and circular dichroism spectra indicate that OEP24 contains seven amphiphilic beta strands. The primary structure of OEP24 shows no homologies to mitochondrial or bacterial porins on a primary sequence basis, and OEP24 is functionally not inhibited by cadaverine, which is a potent inhibitor of bacterial porins. We conclude that OEP24 represents a new type of solute channel in the plastidic outer envelope.

Amino Acid Sequence↗
PubMed1997

Isolation and characterization of an amino acid-selective channel protein present in the chloroplastic outer envelope membrane.

The reconstituted pea chloroplastic outer envelope protein of 16 kDa (OEP16) forms a slightly cation-selective, high-conductance channel with a conductance of Lambda = 1,2 nS (in 1 M KCl). The open probability of OEP16 channel is highest at 0 mV (Popen = 0.8), decreasing exponentially with higher potentials. Transport studies using reconstituted recombinant OEP16 protein show that the OEP16 channel is selective for amino acids but excludes triosephosphates or uncharged sugars. Crosslinking indicates that OEP16 forms a homodimer in the membrane. According to its primary sequence and predicted secondary structure, OEP16 shows neither sequence nor structural homologies to classical porins. The results indicate that the intermembrane space between the two envelope membranes might not be as freely accessible as previously thought.

Amino Acid Sequence↗
PubMed1997

Postimport methylation of the small subunit of ribulose-1,5-bisphosphate carboxylase in chloroplasts.

Electron impact mass spectronomy analysis of the amino-terminal amino acid of the small subunit (SSU) of ribulose-1,5-bisphosphate carboxylase (Rubisco) showed that the amino-terminal methionine residue is post-translationally modified to N-methyl-methionine. Modification of the amino-terminal methionine residue was found in mature SSU proteins from the dicotyledonous plants pea and spinach as well as the monocotyledonous plants barley and corn. SSU methyltransferase is a soluble protein in the chloroplast stroma and accepts heterologously expressed non-methylated SSU as a substrate using S-adenosylmethionine as methyl-group donor. We show that this modification occurs after post-translational uptake of the precursor form of SSU into chloroplasts and processing to its mature size. This reaction represents a new step in the import and assembly pathway of Rubisco holoenzyme.

Chloroplasts↗
PubMed1997

[Prevalence of Echinococcus multilocularis and other metacestodes and cestodes in the muskrat (Ondatra zibethicus LINK 1795) in Lower Saxony].

Aim of the study was to examine the prevalence and regional distribution of Echinococcus multilocularis and other metacestodes and cestodes in muskrats in Lower Saxony, Germany. A total of 991 muskrats with similar numbers from all districts of the country were examined between January and December 1995. E. multilocularis metacestodes were found in 4.1% of the muskrats in the liver and other organs of the abdominal cavity. The majority of the E. multilocularis positive animals came from the south of Lower Saxony, where E. multilocularis is endemic, and single animals from the middle or the northern part of the country. All metacestodes found were fertile. Additionally, metacestodes from T. taeniaeformis were found in the livers of 42.3% of the muskrats, metacestodes from T. crassiceps were present in the abdominal cavity of 2.7%, T. polyacantha in 0.4% and T. martis in 3.4% of the animals. Adult cestodes of the family of the Anoplocephalidae were found in the small intestine of 1.5% of the muskrats. Due to autolysis a species differentiation of the latter was not possible.

Abdomen↗
PubMed1997

[Nematode and trematode fauna of the muskrat (Ondatra zibethicus LINK, 1795) in Lower Saxony].

From January 1995 to December 1995, 991 muskrats were examined for the occurrence and the regional prevalence of nematodes and trematodes. The muskrats were trapped in all parts of Lower Saxony. 77.2% of the studied population were less than one year old, 22.8% were older. The male to female ratio was 54.5% to 45.5%. One genus of nematodes, Trichuris spp., was found in the colon in 1.9% of the animals in the south of the investigated area. A species differentiation was not possible, as exclusively female parasites had been found. Additionally, two genera of trematodes (Echinostoma spp. and Quinqueserialis quinqueserialis) belonging to two different families were detected in 2.5% of the muskrats. In the north of the investigated area the prevalence was significantly higher than in the south. As to the echinostomatides, no species-differentiation was made because, according to KANEV (1985), many echinostomatides have not been described correctly in the past. Some echinostomatides cannot be differentiated until today. There was no statistically significant correlation between parasite infections and sex of the animals. Concerning Echinostoma spp. and Quinqueserialis quinqueserialis, a highly significant correlation was found between the age of the muskrats and the trematode-infections. Young animals were infected more often than older animals, none of the younger animals was infected with Trichuris spp.

Animals↗
PubMed1996

CP12: a small nuclear-encoded chloroplast protein provides novel insights into higher-plant GAPDH evolution.

Higher-plant chloroplast NAD(P)-glyceraldehyde 3-phosphate dehydrogenase (NAD(P)-GAPDH; EC 1.2.1.13) is composed of two different nuclear-encoded subunits, GAPA and GAPB, forming the highly active heterotetrameric A2B2 enzyme. The main difference between these two subunits is a C-terminal extension of about 30 amino acid residues of GAPB. We present cDNA clones for a nuclear-encoded chloroplast protein from pea, spinach and tobacco, which we have named CP12. The mature protein consists of only 74, 75 and 76 amino acid residues, respectively and contains two domains with significant homology to the C-terminal extension of GAPB. Affinity chromatography approaches reveal also a specific interaction between CP12 and chloroplast GAPDH. Northern blot analysis indicates that CP12 is, like plastid GAPDH, expressed in green and also in etiolated leaves. Further homology is observed between CP12 and ORF3, an open reading frame located in the hox gene cluster of Anabaena variabilis. This gene cluster encodes the subunits of the bidirectional NADP(+)-dependent [NiFeS] dehydrogenase. We propose therefore a common evolutionary origin of CP12 and higher-plant chloroplast GAPDH subunit GAPB from the cyanobacterial ORF3.

Amino Acid Sequence↗
PubMed1995

[Requirements of raising game pheasants (Phasianus colchicus sp.) in respect to animal welfare laws].

The present study works for a list of requirements of animal protection on the commercial rearing of common pheasant. Therefore universally valid tags and requirements are evolved for feeding, illumination regiment in the rearing compartments and housing densities and for pheasants freedom from injury. The duty of the veterinary authorities for powerful checkups is pointed out.

Animal Feed↗
PubMed1995

[Comparative studies of the release and ability to survive of game pheasants (Phasianus colchicus sp.) from intensive and extensive husbandry].

Artificially reared pheasants had been released at an age of 10 weeks on two stands in a suitable habitat with a wild pheasant population in Lower Saxony, Germany. Two groups (200 pheasants reared in large fly-aviaries, 200 pheasants reared in dark stables) were bought from commercial breeders who offer pheasants for restocking wild populations. Some of the released pheasants were marked with radio-transmitters. There was no significant difference in survival rate between the two rearing groups. Moreover a significant difference in survival rate between the two releasing points could be find out. Within 32 days 114 (30%) of the 380 released pheasants died mainly by predators e.g. fox/martens (44%) and goshawk (12%). 59% of these refound dead pheasants died already within the first week. 20 pheasants died in the releasing-aviary. Most of the released pheasants alive were re-observed within a diameter of 1000 metres from the releasing points. Only some pheasants dispersed more than 2000 metres. No pheasant released could be observed longer than 5 weeks. We suppose that most of pheasants released died within short time.

Animal Husbandry↗
PubMed1993

[Comparative studies of commercial breeding methods for game pheasants (Phasianus colchicus spec.) with regard to the animal welfare aspects of extensive and intensive husbandry].

The study presents the effects that different rearing methods of commercial pheasantries have on pheasants. The techniques applied by 17 commercial pheasantries in Northern Germany are specified. These techniques were exemplarily simulated on pheasants reared under defined conditions in special aviaries. The results illustrate the impact of the different rearing methods on the condition and constitution on the birds seen from the point of view of animal welfare. Only about 35% (20,400) of all pheasants reared (85,000) in commercial pheasantries were kept under conditions which allowed a physical and behavioural development that nearly complied with the stipulation of the animal protection laws. In approximately 65% of all the pheasants were not enabled to adapt themselves to the food or climate of the habitat they would have to live in after their release. The study proves that most of the currently applied rearing techniques as well as the methods for preventing feather picking are not compatible with the law on the protection of animals.

Adaptation, Physiological↗
PubMed1993

[The lymph vessel system of fallow deer (Dama dama L. 1758)].

In the present study the main lymph vessels of important lymph centres of fallow deer are described in detail and represented radiologically. The lymph flow from the periphery (Ear conch, distal extremity) to the entry into the venous angle is proved by means of simultaneous indirect lymphography (SIL). The vasa afferentia do not lead from the lateral ear conch to the NI. parotideus, as usually described with domestic animals, but run dorsally along the cervical vertebra to the NI. cervicalis superficialis. Therefore the Truncus jugularis does not drain the entire head. Furthermore, in view of the findings obtained with fallow deer, the general formation of a superficial and a deep lymphatic system in the distal zones of the extremities is questionable at least as far as domestic ruminants of comparable size are concerned.

Animals↗
PubMed1993

[The helminth fauna of wild boars of the west Berlin forests].

Samples of muscles and internal organs obtained from 96 wild boars in the forests of West Berlin between September 1989 and August 1990, were examined for helminths. Nine nematode species, Metastrongylus pudendotectus, M. salmi, M. confusus, M. apri, Physocephalus sexalatus, Ascarops strongylina, Globocephalus urosubulatus, Ascaris suum and Trichuris suis belonging to five families could be found. Larvae of Toxocara spp. were isolated from most of the enzymatically digested samples of the gastrointestinal tract. In a few cases juvenile forms of Cysticercus tenuicollis could be identified. Trichinella spiralis and trematodes were not found. The correlation between helminth infection and age and sex of the wild boars as well as time and site of shooting are discussed.

Animals↗
PubMed1992

[Veterinary tasks in nature and species protection].

The present paper is designed to give examples of possible fields of activities for veterinary surgeons in the areas of nature conservation and the protection of species. The committed veterinary surgeon, who is eager to extend his/her specialized knowledge obtained at the university will certainly find a sensible and satisfying occupation in the fields of nature conservation, the protection of species and the environment. Creating the optimum prerequisites for these professional opportunities is yet another reason why public funding of the Institute for Game Research and Ecology is indispensable.

Animal Welfare↗
PubMed1992

[Hunting with traps with regard to animal welfare, species protection and safety].

The present paper critically examines the subject of huntsmanlike hunting with traps as it is practiced in the Federal Republic of Germany. In this context, consideration is given to the aspects of protection of animals, protection of species and safety for people and domestic animals. Hunting with traps is regarded a necessary element within the legal duties of game preservation. Basically, the focus is placed on efficient hunting of predatory animals that are mainly active at night such as foxes, raccoons and martenlike beasts. Trapping instruments and catching methods that respect the above mentioned aspects are presented. The legislator is requested to set up binding quality standards for the traps to be used. Special training for all trappers with a final examination in theory and practice is considered inevitable.

Animal Welfare↗
PubMed1991

Experimental transplantation of vascularized autologous and allogenic bone grafts for mandibular defects. Anatomical, immunological and surgical basis for vascularized bone transfer in the Göttingen minipig.

The Göttingen minipig serves as a suitable animal model for studying microsurgically reanastomosed iliac crest grafts for reconstruction of bone defects of the mandible. Because of the vascularization pattern of the hip bones of the Göttingen minipig, the cranioventral region of the ilium is especially suitable as a donor site. The separate vascularization of this area allows the excision of a bone block with sufficient volume, mechanical strength and a reliable vascular pedicle. The high degree of immunological variability of the minipigs demonstrated by isoelectric focusing and subsequent immunoblotting of lymphocyte membrane proteins offers possibilities for allogenic transplantation models. The surgical technique of harvesting and transplantation of the bone graft is described in detail.

Animals↗