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H Böhme

Publications and source records attributed to H Böhme.

At least 19 recordsLinked to original sources
PubMed1998

The isiB gene encoding flavodoxin is not essential for photoautotrophic iron limited growth of the cyanobacterium Synechocystis sp. strain PCC 6803.

When iron becomes limiting, Synechocystis 6803 induces the synthesis of flavodoxin. As a basis for genetic analysis, the flavodoxin-encoding isiB gene of Synechocystis 6803 was cloned and sequenced. The isiB gene was disrupted by insertion of an interposon within the isiB coding region resulting in two Synechocystis 6803 mutant strains, CKF-I and CKF-II. They were distinguished from each other by the orientation of the kanamycin resistance cassette. Photoautotrophic growth of the mutant strains under iron limiting conditions, which are sufficient for induction of flavodoxin in the wild-type cells, demonstrated that IsiB was not essential for Synechocystis 6803.

Bacterial Proteins↗
PubMed1998

Interaction of positively charged amino acid residues of recombinant, cyanobacterial ferredoxin:NADP+ reductase with ferredoxin probed by site directed mutagenesis.

The petH genes encoding ferredoxin:NADP+ reductase (FNR) from two Anabaena species (PCC 7119 and ATCC 29413) were cloned and overexpressed in E. coli. Several positively charged residues (Arg, Lys) have been implicated to be involved in ferredoxin binding and electron transfer by cross-linking, chemical modification and protection experiments, and crystallographic studies. The following substitutions were introduced by site-directed mutagenesis: R153Q, K209Q, K212Q, R214Q, K275N, K430Q and K431Q in Anabaena 29413 FNR, and R153E, K209E, K212E, R214E, K275E, R401E, K427E, and K431E in Anabaena 7119 FNR. Comparison of the diaphorase activities, the specific rates of ferredoxin dependent NADP(+)-photoreduction and cytochrome c reduction catalyzed by FNR showed that all these amino acid residues were required for efficient electron transfer between FNR and ferredoxin. Replacement of any one of these basic residues produced a much more pronounced effect on the cytochrome c reductase activity, where FNR, reduced by NADPH, acted as electron donor, than in the reduction of NADP+ by photosystem I via FNR. A mutation involving the replacement of positive charge by a neutral amide produced in all cases a smaller inhibitory effect on the activity than a charge reversal mutation. In addition, it has been found that R214 was necessary for stable integration of the non covalently bound FAD-cofactor.

Amino Acids↗
PubMed1998

[Effects of inpatient client-centered psychotherapy in various illness: 1-year follow-up].

The long-term effect (1-year-follow-up) of an inpatient client-centred psychotherapy programme was evaluated in 202 severe and chronically disturbed patients with a bread diagnose range (ICD-10 F1-F6). These 202 patients represented 74% of a total of 272 patients who had originally been examined and tested at admission and had now been re-identified after a follow-up of one year. Patients were investigated via Clinical Global Impressions (CGI), Bech-Rafaelsen-Melancholia-Scale (BRMES) and the Personality Inventory (Giessen-Test). Severity of illness, depressivity and self-and-other acceptance improved significantly; social incompetence was especially reduced in patients who had personality disorders. The range of effects reached from good to very good improvement: the magnitude of effect on social variables is probably even under estimated due to high pre-therapy variance. At follow-up 68% of the patients were in occupation or professional education. 32% needed no further treatment. Readmission rate was 14%. Results are discussed with regard to specific client-centred therapy.

Adaptation, Psychological↗
PubMed1997

[Defenses in rating scales and therapy success].

Evaluation of psychotherapeutic or psychopharmacological treatment frequently uses rating scales without regard for patient's defensiveness. This study demonstrates on 309 psychotherapy patients treated with inpatient client-centered therapy and followed-up 1 year after treatment that defensiveness, measured with validity scales of personality inventories MMPI-K, FPI-R and Giessen-Test, influences ratings (scales CGI, HAMA, HAMD, BRMES) before and after therapy. Patients who deny psychopathology on admission do so at discharge and to some extent at follow-up. The extent of effect is significantly diminished with an increase in frankness in these patients, indicated by the significant improvement in validity scales. Inpatient client-centered psychotherapy improved defensiveness in the case of initial self-criticism and diminished it in the case of initial retentiveness.

Adult↗
PubMed1997

Identification and characterization of the nifV-nifZ-nifT gene region from the filamentous cyanobacterium Anabaena sp. strain PCC 7120.

The nifV and leuA genes, which encode homocitrate synthase and alpha-isopropylmalate synthase, respectively, were cloned from the filamentous cyanobacterium Anabaena sp. strain PCC 7120 by a PCR-based strategy. Since the N-terminal parts of NifV and LeuA from other bacteria are highly similar to each other, a single pair of PCR primers was used to amplify internal fragments of both Anabaena strain 7120 genes. Sequence analysis of cloned PCR products confirmed the presence of two different nifV-like DNA fragments, which were subsequently used as nifV- and leuA-specific probes, respectively, to clone XbaI fragments of 2.1 kbp (pOST4) and 2.6 kbp (pOST2). Plasmid pOST4 carried the Anabaena strain 7120 nifV-nifZ-nifT genes, whereas pOST2 contained the leuA and dapF genes. The nifVZT genes were not located in close proximity to the main nif gene cluster in Anabaena strain 7120, and therefore nifVZT forms a second nif gene cluster in this strain. Overlaps between the nifV and nifZ genes and between the nifZ and nifT genes and the presence of a 1.8-kb transcript indicated that nifVZT might form one transcriptional unit. Transcripts of nifV were induced not only in a nitrogen-depleted culture but also by iron depletion irrespective of the nitrogen status. The nifV gene in Anabaena strain 7120 was interrupted by an interposon insertion (mutant strain BMB105) and by a plasmid integration via a single crossover with a nifV internal fragment as a site for recombination (mutant strain BMB106). Both mutant strains were capable of diazotrophic growth, and their growth rates were only slightly impaired compared to that of the wild type. Heterologous complementation of the Rhodobacter capsulatus nifV mutant R229I by the Anabaena strain 7120 nifV gene corroborated the assumption that Anabaena strain 7120 nifV also encodes a homocitrate synthase. In contrast, the Anabaena strain 7120 leuA gene did not complement the nifV mutation of R229I efficiently.

2-Isopropylmalate Synthase↗
PubMed1997

The benefit of an insight-oriented and experiential approach on panic and agoraphobia symptoms. Results of a controlled comparison of client-centered therapy alone and in combination with behavioral exposure.

BACKGROUND: It is a common view that psychodynamic treatment does not help much to ameliorate the symptoms of panic and agoraphobia. The effects of an insight-oriented treatment on central anxiety symptoms are the subject of the present controlled study. METHODS: Forty patients with severe panic and agoraphobia were admitted to an inpatient anxiety treatment program. Most of the patients had been treated by pharmacological means unsuccessfully. The patients were randomly assigned to pure client-centered therapy or to additional behavioral exposure treatment. Client-centered and behavioral agoraphobia manuals were used. The patients were examined on admission, at discharge and at 3, 6, and 12 months follow-up for panic (Structured Clinical Interview for DSM III-R--SCID), anxiety (Hamilton Anxiety Scale), agoraphobia (SCID, Fear Survey Schedule), and depressive (Hamilton Depression Scale) symptoms. RESULTS: Both client-centered treatment and a combination with exposure treatment reduced panic, avoidance and depressive symptoms significantly. For a short period the combined treatment was superior in patients' coping actively with anxiety and improving agoraphobic symptoms. However, at 1-year follow-up there was no further difference in the reduction of anxiety and depressive symptoms. CONCLUSIONS: The results are discussed with regard to the combination of these forms of therapy and to widespread skepticism about the efficacy of insight-oriented treatment.

Adult↗
PubMed1996

Glutamate 94 of [2Fe-2S]-ferredoxins is important for efficient electron transfer in the 1:1 complex formed with ferredoxin-glutamate synthase (GltS) from Synechocystis sp. PCC 6803.

We have analyzed the role of critical amino acid residues involved in the interaction between ferredoxin and ferredoxin-glutamate synthase (GOGAT) encoded by the gltS gene from the cyanobacterium Synechocystis sp. PCC 6803. Our results indicated that the glutamate 94 residue of Anabaena 7120 ferredoxin (= E92 of the Synechocystis 6803 ferredoxin) was necessary for an efficient electron transfer to GOGAT comparable to ferredoxin:NADP-reductase, nitrite reductase and nitrate reductase [Schmitz and Böhme (1995) Biochim. Biophys. Acta 1231, 335-341]. The K(m) value determined for wt-ferredoxins and mutant E94Q (and E92Q) was 1 muM, respectively, and activity loss of E94Q was due to a lowered Vmax. Exchange of residue F65 for aliphatic substitutions, which was crucial to electron transfer to ferredoxin:NADP-reductase and nitrite reductase, exhibited only small effects on glutamate synthase-dependent activity while heterocyst ferredoxin and flavodoxin were almost inactive as electron donors. In contrast to data reported for the spinach system, the stoichiometry of the cross-linked complex between ferredoxin and glutamate synthase was 1:1.

Amino Acid Oxidoreductases↗
PubMed1996

Long tandemly repeated repetitive (LTRR) sequences in the filamentous cyanobacterium Anabaena sp. PCC 7120.

Nucleotide sequence analysis of the DNA region carrying transposon Tn5-1087b from the Anabaena 7120 nitrogen fixation-deficient mutant YC16 revealed the presence of a novel repeated DNA element in cyanobacteria designated long tandemly repeated repetitive (LTRR) sequence. The LTRR element is 37 bp long and contains an inverted repeat sequence. 17 copies of the LTRR element, 13 of which were completely identical, were identified within a 1.3 kb DNA fragment, which was flanked by two divergently transcribed genes homologous to bacteriophage T4 'gene 15' and Rhizobium meliloti exoD, respectively. LTRR-like sequences occur in several DNA regions in Anabaena 7120 and in other cyanobacteria. Furthermore, the presence of an LTRR-like DNA region in mitochondrial plasmids of Vicia faba indicates strong conservation of such structures during evolution.

Amino Acid Sequence↗
PubMed1996

Expression of ferredoxin-NADP+ reductase in heterocysts from Anabaena sp.

The expression of ferredoxin-NADP+ reductase (FNR) from Anabaena sp. PCC 7119 in heterocysts and vegetative cells has been quantified. Specific reductase activity in heterocysts was approximately 10 times higher than in vegetative cells, corresponding to the increased FNR protein content. This was confirmed by immunoquantification of the FNR protein from whole filaments of Anabaena sp. PCC 7120 grown in media with and without combined nitrogen. Transcription of the petH gene was markedly enhanced in the absence of combined nitrogen. This suggests that the increased RNA level is mainly responsible for the up-regulation of FNR in heterocysts. As has been observed for nif genes, iron deficiency also increased transcription of petH. Characterization of the FNR purified from isolated heterocysts showed no detectable differences from the enzyme from vegetative cells. Although nitrogen stress was a key regulatory factor, localization of the petH gene in the genomic map of Anabaena PCC 7120 showed that this gene is not physically associated with the nif cluster.

Anabaena↗
PubMed1995

Different patterns of sexual dysfunctions associated with psychiatric disorders and psychopharmacological treatment. Results of an investigation by semistructured interview of schizophrenic and neurotic patients and methadone-substituted opiate addicts.

Little is known about sexual dysfunctions associated with psychiatric disorders and psychopharmacological treatment. In the present study schizophrenic patients (n = 45, mostly under neuroleptic treatment), neurotic patients (n = 50, mostly treated without medication), methadone-substituted opiate addicts (n = 37), and normal controls (n = 41) were included. They were interviewed with the aid of a sex-differentiated semistructured questionnaire on sexual function. All the methadone-substituted opiate addicts and nearly all the schizophrenic patients suffered from dysfunctions in at least one criterion. The three clinical groups differed significantly from the controls in sexual interest, emotional arousal, physiological arousal (erectile function/vaginal lubrication), performance (ejaculatory function/vaginism, dyspareunia), and orgasm satisfaction. Characteristic patterns of dysfunction were found in the male patients. The schizophrenic patients had significantly more dysfunctions of interest, physiological arousal, performance, and orgasm than the controls. Emotional arousal, erectile and ejaculatory functions, and orgasm satisfaction were impaired more frequently in the male schizophrenics than in the neurotic patients. Reduced sexual interest, emotional arousal, and orgasm satisfaction were reported more frequently by the methadone-substituted opiate addicts than by the neurotic men. Emotional arousal was even more frequently reduced than in the schizophrenic men. There was no correlation between sexual dysfunction and particular neuroleptics or neuroleptic or methadone dosage. The results are compared with the literature and suggestions made for further investigations.

Adult↗
PubMed1995

[How can acceptance by psychiatric patients of group psychotherapy be improved? An empirical study of the effect of combined individual and group psychotherapy on attitude to group psychotherapy].

This study investigates whether the sceptic attitude of many psychiatric patients to group therapy can be improved by a combined individual and group therapy program. The investigation was made on 50 patients, most of them with neurotic disorders, partly with secondary alcohol or substance abuse as well as some schizophrenic patients. Before admittance to the psychotherapy program enquiries were made by means of a questionnaire, about what subject they would like to speak in the individual or group therapy sessions. The results differ significantly dependent on sociodemographic and illness related factors. A second examination after discharge reveals an ameliorated attitude concerning group therapy in nearly all central themes. Thus, one of the important goals of in-patient psychotherapy has been achieved to improve patients ability to receive out-patient group therapy.

Adult↗
PubMed1994

Characterization of a B-CLL derived IgM-lambda antibody expressing typical features of a NPAB.

A human IgM-lambda hybridoma (CB-HB) was established from chronic lymphocytic leukaemia (CLL) B-cells. Immunochemical and molecular characterization of the monoclonal antibody (mab) produced by the CB-HB cells offered typical features of natural polyreactive antibodies (NPAPs) found in fetal and healthy adult organisms. In particular, the CB-HB mab reacted with different self and foreign (viral and bacterial) antigens when tested in three independent systems (solid- and fluid-phase ELISA, Western blot) showing binding constants in a range from 1.9 x 10(-7) to 7.5 x 10(-8) mol/l to four antigens chosen. In addition, the CB-HB mab binding could be inhibited by a rabbit polyclonal antiserum specific for a common idiotype (Id 102) on human polyreactive (auto)antibodies. The variable region of the CB-HB mab was found to be encoded by unmutated copies of germline genes. Interestingly, the VH-DP10 (51p1) segment, encoding for the autoantibody-associated G6-cross reactive idiotype frequently expressed on both fetal and malignant B-cells, was found to be used with a V segment (VLO11). Collectively these data imply that cells belonging to the natural polyreactive B-cell repertoire undergo malignant transformation. A stimulation by autoantigens or common foreign antigens may be involved.

Antibodies, Monoclonal↗
PubMed1994

Transcriptional and translational analysis of ferredoxin and flavodoxin under iron and nitrogen stress in Anabaena sp. strain PCC 7120.

In Anabaena sp. strain PCC 7120, vegetative cell ferredoxin synthesis under iron starvation was repressed 25-fold, whereas heterocyst ferredoxin synthesis decreased only 2.8-fold. Induction of flavodoxin under iron depletion was independent of the availability of combined nitrogen. Under iron stress but in the presence of combined nitrogen, fdxH and nifH genes were transcriptionally active; although excision of the 11-kb element seemed to be completed, nitrogenase activity and the fdxH gene product were not detectable.

Adaptation, Biological↗
PubMed1994

Characterization of the genome region encoding an fdxH-type ferredoxin and a new 2[4Fe-4S] ferredoxin from the nonheterocystous, nitrogen-fixing cyanobacterium Plectonema boryanum PCC 73110.

A genomic DNA region with four consecutive open reading frames, including an fdxH-type gene, has been sequenced and initially characterized for the nonheterocystous nitrogen-fixing cyanobacterium Plectonema boryanum PCC 73110. The fdxH gene encodes a [2Fe-2S]-type ferredoxin, 98 amino acids in length, with a deduced molecular mass of 10.9 kDa. Conserved residues include two characteristic lysines at positions 10 and 11, shown recently to be important for interaction with nitrogenase reductase (S. Schmitz, B. Schrautermeier, and H. Böhme, Mol. Gen. Genet. 240:455-460, 1993). The gene is transcribed only under anaerobic nitrogenase-inducing conditions, whereas the Plectonema petF gene, encoding a different (type 1) [2Fe-2S] ferredoxin, is only transcribed in cultures growing with combined nitrogen. The fdxH gene was expressed in Escherichia coli as a holoprotein. The purified protein was able to effectively donate electrons to cyanobacterial nitrogenase, whereas PetF from the same organism was not. The occurrence of FdxH in the nonheterocystous genus Plectonema demonstrates for the first time that FdxH-type ferredoxins are not exclusively expressed within heterocysts, as is true for cyanobacteria differentiating these cells for nitrogen fixation under aerobic growth conditions. Two open reading frames that precede fdxH have high similarity to those found at a corresponding location in Anabaena sp. strain PCC 7120. In the latter organism, they are transcribed only under nitrogen-fixing conditions, but the functions of their gene products remain unclear (D. Borthakur, M. Basche, W. J. Buikema, P. B. Borthakur, and R. Haselkorn, Mol. Gen. Genet. 221:227-234, 1990). An fdxB-type gene encoding a 2[4Fe-4S] ferredoxin not previously identified in cyanobacteria is located immediately downstream of fdxH in P. boryanum.

Amino Acid Sequence↗
PubMed1994

[Change in causal attributions and coping caused by inpatient client-centered psychotherapy].

During 3-month client-centered hospital treatment 108 patients with neurotic depression, anxiety disorders and other neuroses (DSM-III-R) recovered from depressivity (Giessen-Test, MES), negative attributional styles and regressive coping (KCF). Gains were maintained over follow-up one and two years after therapy. Not only cognitive, but also rogerian psychotherapy leads to significant increment in cognitive coping efforts, even when grade of depressivity is regarded. Attributional style and coping strategies depended on grade of depressivity and status of patient (admission or follow-up); cognitions did not discriminate dysthymic (depressive) patients from other neurotic disorders.

Adaptation, Psychological↗