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H Böhme

Publications and source records attributed to H Böhme.

At least 19 recordsLinked to original sources
PubMed1992

Crystallization and preliminary analysis of oxidized, recombinant, heterocyst [2Fe-2S] ferredoxin from Anabaena 7120.

The [2Fe-2S] ferredoxin produced in the heterocyst cells of Anabaena 7120 plays a key role in nitrogen fixation, where it serves as an electron acceptor from various sources and an electron donor to nitrogenase. Crystals of recombinant heterocyst ferredoxin, coded for by the fdx H gene from Anabaena 7120 and overproduced in Escherichia coli, have been grown from ammonium sulfate solutions and are suitable for high resolution X-ray crystallographic analysis. They belong to the hexagonal space group P6(1) or P6(5) with unit cell dimensions of a = b = 44.2 A and c = 80.6 A. The crystals contain one molecule per asymmetric unit and diffract to a nominal resolution of 1.6 A. The molecular structure of this heterocyst ferredoxin is of special interest in that 4 of the 22 amino acid positions thought to be absolutely conserved in nonhalophilic ferredoxins are different and, based on amino acid sequence alignments, three of these positions are located in the metal-cluster binding loop. Consequently, a high-resolution X-ray analysis of this [2Fe-2S] ferredoxin, and subsequent three-dimensional comparisons with other known ferredoxin models, will provide new insight into structure/function relationships for this class of redox proteins.

Ammonium Sulfate↗
PubMed1991

[What is the result of an inpatient treatment program with client-centered psychotherapy emphasis in patients with agoraphobia and/or panic? Results of a 1-year follow-up].

29 of 31 patients with agoraphobia and/or panic-disorder (DSM-III R), treated with an inpatient therapy program with client-centered foundation, could be investigated on a one-year follow up. The investigation was performed by means of the Angst-Katamnese-Fragebogen (AKF), Clinical Global Impressions (CGI), Freiburger Persönlichkeits Inventar (FPI) and Fear Survey Schedule (FSS). On the whole about 2/3 of the patients had a good or very good outcome concerning central anxiety symptoms (panic and agoraphobia). In most of the cases favourable changes of the mental state, interpersonal relationship and personality development were found. The results indicate that an insight orientated and experiential client-centered therapy program helps to reduce anxiety symptoms and to diminish the risk of negative consequences (alcohol and drug abuse).

Adult↗
PubMed1988

Molecular cloning and nucleotide sequence analysis of the gene coding for heterocyst ferredoxin from the cyanobacterium Anabaena sp. strain PCC 7120.

In heterocysts of the filamentous cyanobacterium Anabaena 7120 a specific [2Fe-2S] ferredoxin is synthesized, serving as immediate electron donor to nitrogenase. The structural gene for this heterocyst ferredoxin, fdxH, was isolated from a recombinant lambda library, using an oligonucleotide probe derived from a unique segment of the N-terminal amino acid sequence of the purified protein. The sequence of the entire fdxH coding region was determined including 3' and 5' flanking sequences. Assuming proteolytic cleavage of the first methionine residue, the molecular weight of Anabaena 7120 heterocyst ferredoxin is 10,806. Compared with the ferredoxin from vegetative cells, 47 out of 98 amino acid residues are different, including conversions within a highly conserved region responsible for binding of the iron-sulfur cluster. Northern hybridization with a 0.64 kb EcoRI DNA fragment containing the entire fdxH gene indicated two major transcripts of 0.59 and 1.85 kb, which are expressed at a late stage of heterocyst differentiation. By S1 nuclease digestion and primer extension a possible start site of transcription was mapped, 132 bp upstream of fdxH; however, neither a typical Escherichia coli nor nif-type promoter sequence was apparent. Southern hybridization detected only one copy of the fdxH gene in the Anabaena 7120 genome. FdxH is located approximately 7 kb downstream from the nifHDK gene cluster.

Amino Acid Sequence↗
PubMed1987

[Oxygen supply and oxygen uptake by skeletal muscle in acute arterial circulatory disorders--an experimental study in the dog].

The oxygen supply and the oxygen uptake of the ischemic skeletal muscle were defined in rest and by loading in experimental studies in dog. About 72% of the supplied arterial oxygen was taken up from the ischemic skeletal muscle in rest in opposite to 84.7% by loading. Therewith the authors found an essential higher value as supposed in literature so far. The absolute value of the oxygen uptake of the normally circulated skeletal muscle with 0.14 ml O2/min/100 g is small in contrast to the highly differentiated parenchymatous organs. An adaptation to an anaerobic metabolism is assumed by the authors in case of falling below the critical boundary value of 0.1 ml O2/min/100 g in skeletal muscle.

Animals↗
PubMed1986

[pH measurement in tissue--a reliable criterion for the registration of acute arterial circulatory disorder in animal experiments].

An arterial ischemia was carried out step by step in the right pelvic extremity of the dog. The ph level was measured continuously in the lateral vastus of the femoris muscle on both sides by means of a glass-one-rod measuring equipment. The pH value decreased to 6.43 ninety minutes after a total interruption of the arterial circulation. The initial value amounted to 7.20. The tissue-pH-values increase quickly during the following phase of recirculation.

Animals↗
PubMed1985

[Energy requirement for the maintenance and utilization of energy convertible to protein and fat deposits in piglets].

In respiration experiments with 16 piglets the effect of feeding level on energy metabolism was studied with the aim of estimating energy requirement and costs of protein and fat deposition. Four groups of 4 animals each were fed on different levels of digestible protein and metabolisable energy (ME). Group 1 was fed intensively, whereas the piglets of group 2, 3 and 4 received 92, 76 and 55% respectively of the amounts given to group 1. In the group 1-4 mean daily weight gain was 457, 437, 360 and 205 g respectively. As a consequence the rearing period increased from 44 days to 46, 56 and 98 days. The variation in feed intake affected not only significant differences in energy deposition but also changes in gain composition. In the groups 1-4 the average energy deposition was 4.2 MJ, 4.0 MJ, 3.0 MJ and 1.4 MJ per day and protein gain exceeded fat gain in all groups. Estimations of energy requirement for maintenance were carried out by means of multiple regression analysis using different models. As a result a value of 428 MJ ME per kg live weight 0.75 was obtained and the models used have hardly shown any influence. It seems that higher values for maintenance requirement, as formerly published, are due to different conditions of livestock management, such as temperature. For all groups the average efficiency of ME-utilisation for growth was 0.77, ranging from 0.73 to 0.82. The variation can be attributed to the changes in protein and fat formation. The groups with a higher proportion of protein in the accretion utilised metabolisable energy more efficiently than the intensively fed group 1 with the highest proportion of fat, the difference between the groups being in the range from 0.73 to 0.82. The efficiency of ME-utilisation for protein deposition was calculated to be 0.83 and for fat deposition 0.73. As a higher coefficient for fat formation may be expected in the light of the high fat content in the ration, calculations with an assumed coefficient from 0.75 and 0.80 had been carried out, showing that the efficiency of ME-utilisation for protein gain would only decrease to 0.79 and 0.73 respectively. According to these results the statement must be called in question, that the energetic efficiency of protein deposition of about 50 to 55% - as measured in numerous experiments mainly with older pigs - can generally be accepted.

Animal Feed↗
PubMed1979

[Possibilities of assessing cerebrovascular disease by audiometry: Comparison with Doppler ultrasound in the assessment of extracranial vascular occlusion (author's transl)].

Discrimination loss in the speech-audiogram (one-syllable test) was tested on 61 patients with cerebrovascular disease due to extracranial vessel stenosis in the area of the carotid artery distribution. In 44 of the patients (extracranial vessel stenosis or occlusion) the results were compared with the carotid angiogram and Doppler ultrasonography. There was agreement between loss of discrimination, localisation by angiography, ultrasound results and the relevant clinical findings in 32 of 36 patients. In 17 patients audiometry was performed before and after surgical reconstruction of the internal carotid artery. Among 13 patients in whom the results could be assessed, discrimination improved postoperatively in 11 (at least 20% in six, at least 10% in five). The combination of ultrasound and audiometry can be used as a screening method in unclear cases to evaluate suspected cerebrovascular disease, simplify indications for carotid angiography, and used serially, follow any further development of the vascular disease.

Aged↗