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Title ofthe paper: Boar fattening with different protein supply in the diet In the literature numerous studies are found that proof a superior fattening performance and carcass composition for boars compared to female and castrated pigs. The results in the feeding experiment presented here do not confirm this to the same extend. Even with a high protein and lysine supplementation growth performance of boars was lower than in females. Lean content was determined by FOM grading which might underestimate the boars. Lean to fat ratio (areas of M. long dorsi and back fat) however was significantly different between castrates and all boar groups due to the reduced fat deposition. Sensoric tests detected significant boar taint in the majority ofthe samples from male carcasses. Considering the tendency on the market for increasing carcass weights and the risk of boar taint in heavier pigs boar fattening can not be recommended in Germany.

Zusammenfassung 14 Dermatophyten–Arten wurden auf Haar von 7 verschiedenen Haustieren und dem des Menschen in Losungen mit unterschiedlichem Nahrstoffgehalt kultiviert und die Form des Haarbefalls nach 20 bzw. 30tagiger Versuchszeit beobachtet. In einem nahrstoffreichen Medium wurden die Haare seltener von Pilzen angegrif–fen als in einem nahrstoffarmen. Auf Schafwolle, Kaninchen– und Meerschwei–chenhaar traten in Folge des Pilzbefalls Lockerung und Zerstorung der Kortex–struktur sowie oberflachliche Erosionen des Haarschaftes, nur selten jedoch Per–forationen der Haarrinde auf. In Kulturen mit Schweineborsten, Pferde– und Menschenhaar fanden sich haUufig Perforationsorgane der Pilze in den Haar–partikeln. Die Neigung zur Ausbildung von Perforationsorganen ist bei den einzelnen Dermatophyten–Arten unterschiedlich groβ. Die moglichen Ursachen fur das Auftreten der verschiedenen Befallsformen und ihre Beeinfluβbarkeit durch Umweltbedingungen werden diskutiert.

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.

In cyanobacteria an increasing number of low potential electron carriers is found, but in most cases their contribution to metabolic pathways remains unclear. In this work, we compare recombinant plant-type ferredoxins from Anabaena sp. PCC 7120, encoded by the genes petF and fdxH, respectively, and flavodoxin from Anabaena sp. PCC 7119 as electron carriers in reconstituted in vitro assays with nitrogenase, Photosystem I, ferredoxin-NADP(+) reductase and pyruvate-ferredoxin oxidoreductase. In every experimental system only the heterocyst ferredoxin catalyzed an efficient electron transfer to nitrogenase while vegetative cell ferredoxin and flavodoxin were much less active. This implies that flavodoxin is not able to functionally replace heterocyst ferredoxin. When PFO-activity in heterocyst extracts was reconstituted under anaerobic conditions, both ferredoxins were more efficient than flavodoxin, which suggested that this PFO was of the ferredoxin dependent type. Flavodoxin, synthesized under iron limiting conditions, replaces PetF very efficiently in the electron transport from Photosystem I to NADP(+), using thylakoids from vegetative cells.

The formation of progesterone and 1-dehydroprogesterone from cholesterol in fermentation cultures of Mycobacterium aurum ATCC 25790 was studied with the aim of clarifying the microbial pathway. The C22-intermediate (20S)-20-carboxy-1,4-pregnadien-3-one was microbiologically converted via the undetectable corresponding aldehyde into the C22-alcohol. However in the fermentation broth without microorganisms, but containing 2,2'-bipyridyl and copper ions, synthetically prepared C22-aldehyde was oxidized to the corresponding C21-compound 1-dehydroprogesterone, suggesting that the enzymatically originated C22-aldehydes may be immediately chemically oxidized to the corresponding C21-ketones.

Many proteins (including nitrogenase) require the assistance of molecular chaperones in order to become properly folded and assembled as oligomeric structures. As a prerequisite to analyze the role of chaperones in heterocyst differentiation and nitrogen fixation in cyanobacteria, we have isolated the dnaK gene region from A. variabilis. Nucleotide sequence analysis of an 8 kb DNA fragment revealed the presence of three open reading frames (dnaK, dnaJ1, and dnaJ2) reading in the same direction. The three coding regions are separated by 192 bp and 622 bp, respectively. In contrast to many other bacteria, the dnaK gene of A. variabilis is not preceded by a grpE-like gene. Instead, a DNA sequence showing strong homology to the -35/-10 consensus promoter of E. coli was identified 128 bp upstream of the dnaK start codon. The 128 bp DNA region contains two sequences of dyad symmetry, which are different from the highly conserved CIRCE element, which has been found upstream of many chaperone-encoding genes in other bacteria.

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.

Analyses of glycosylation of the human monoclonal IgGl λ antibody (mab) CBGA1 are shown. The mab producing cell line was obtained by EBV transformation of peripheral blood lymphocytes of a healthy donor fused to the heteromyeloma CB-F7 (1). The human CBGA1 mab belongs to the multireactive group of natural antibodies, described as potential useful for treating bacteremic infections of gram negative bacteria as Pseudomonas aeruginosa, Klebsiella and E. coli (2). Two grams of mab were produced using suspension and hollow fibre bioreactors. The hollow fibre bioreactor was shown to be the most efficient system. Furthermore Fab- and Fc-fragments of the purified mab were prepared and analyzed. We found noteworthy heterogeneity of CBGA1 in SDS-PAGE and IEF. SDS-PAGE and lectinblot were used for glycosylation analysis. In addition to the N-glycosylation of the Fc part, a Fab fragment glycosylation could be shown. We found that both the VH and VL are glycosylated. The glycosylation pattern of the Fc fragment differs from that of the Fab. The VH-N-glycosylation site was located at position Asn 75 in frame III.

Filamentous cyanobacteria such as Anabaena differentiate cells specialized for nitrogen fixation, called heterocysts. A large number of mutants of Anabaena 7120, defective in heterocyst differentiation, were isolated. For some of these, the gene that complements the mutation has been identified by conjugation with a cosmid library of wild-type DNA fragments. One early-acting gene has been sequenced. This gene, het R, is required to initiate differentiation, has no function in vegetative cells, and when present in extra copies in wild-type cells, causes the formation of multiple heterocysts. The organization of the genes for nitrogen fixation in Anabaena was also studied. The nif gene region of vegetative cell DNA of Anabaena 7120 carries two interrupting elements: an 11-kb element inserted near the carboxy terminus of the nifD gene and a 55-kb element inserted near the nifS gene. Both elements are flanked by directly repeated sequences within which site-specific recombination occurs during heterocyst differentiation. The result of these recombinations, in each case, is precise excision of the element and fusion of the heterocyst chromosome. In the case of the 11-kb element, excision leaves behind the intact nifHDK operon. The other rearrangement yields the nifB fdxN nifSU operon, where niifSU have the same significance as their Klebsiella counterparts.

DNase deficient mutants of Proteus mirabilis selected for reduced toluene induced DNA degradation were isolated. Their defect in DNA degradation was shown not only after treatment by toluene but also in crude extracts after cell disintegration by ultrasonic and in untreated starved cultures. The degradation mutants behave just as the wild type with respect to their in vivo functions proofed. The results indicate that the affected DNase does not have an essential function in vivo but acts in postmortem DNA degradation. Probably, the DNase in question concerns the endonuclease I of P. mirabilis described by GOEBEL and HELINSKI (1971 a, b).

The task of this work was the establishment of an effective transfer system for F'-plasmids from Escherichia coli to Proteus mirabilis. It is shown that cells of PG VI act as recipients in crosses with E. coli F' strains but with a low transfer rate of the plasmid. The presumption that a restriction -- modification system in P. mirabilis was the only reason for the low transfer could not be confirmed. An indirect selection method was developed to isolate P. mirabilis cells which are better recipients. Conjugation experiments showed that the isolated mutants had a better recipient capacity (increase of about 100). This is true not only for the transfer of a F'-plasmid but also for a R-plasmid. The stability of these plasmids in the mutant cells, however, was much lower than in the wild type.

1. Mit Chrysosporium keratinophilum, Chr. evolceanui, Arthroderma quadrifidum, A. curreyi und Anixiopsis stercoraria haben wir Untersuchungen uber Waschstum, Morphologie des Haarbefalls, Keratinolyse und Enzymausscheidung bei Kultur der Pilze in einer mineralischen Basisnahrlosung mit Haarpartikeln als Kohlenstoff-Stickstoff-Quelle wahrend einer Versuchsdauer von 77 Tagen ausgefuhrt. 2. Alle diese Pilze griffen Haar mit sogenannten Perforationsorganen, senkrecht zur Haarachse vordringenden, keiflormigen Mycelzapfen, und nicht mit sogenannten Bohrhyphen, ebenfalls senkrecht eindringenden, schmalen, geraden Hyphen an. Daneben kamen auch oberflachliche Lasionen der Haarrinde und Lockerung ihrer Struktur vor. Die Haarbefallsform durch diese apathogenen, keratinophilen Bodenpilze entspricht also der vieler Dermatophyten. 3. Das Ausmas des Keratinabbaues durch die apathogenen Bodenpilze war zwar unterschiedlich (26–49% des gegebenen Keratins) dabei aber keinesfalls niedriger als durch pathogene Dermatophyten (28–40%). 4. Die Pilze veranderten den pH-Wert der Nahrlosung (Ausgangswert 5,2) zum Schwachalkalischen hin (Endwert 8,1). pH 7 wurde bereits 14–21 Tage nach Versuchsbeginn erreicht. Diese Alkalisierungstendenz ist ein typisches Merkmal proteino- besonders keratinophiler Pilze. 5. Alle Pilze schieden Proteinasen aus, deren Aktivitat/mg Mycel keine direkte Korrelation zur Intensitat der Keratinolyse erkennen lies. In der Diskussion der Ergebnisse haben wir dieses Phanomen und seine vermutlichen Ursachen ausfuhrlich besprochen. 6. In den Kulturfiltraten samtlicher Pilze haben wir alkalische Phosphatase (pHopt. 8,5) nachgewiesen. Die Aktivitat/mg Mycel war fur die einzelnen Pilzarten resp.-stamme relativ spezifisch. Da in keratinisiertem Milieu freies Phosphat im allgemeinen nur in Spuren vorhanden ist, vermitteln Phosphatasebestimmungen Hinweise auf potentielle Existenzchancen der Pilze in Keratinen.

1. Es wurde die Immunreaktion der Mausestamme BSVS und BRVR gegen lyophilisiertes Hirnantigen untersucht. Alle Tiere des Stammes BSVS entwickelten allergische Encephalomyelitis, wahrend keines der Tiere des Stammes BRVR erkrankte. 2. Bei keinem der beiden Stamme konnten komplementbindende oder antinucleare Antikorper nachgewiesen werden. 3. Stamm BRVR zeigte ein signifikant hoheres Thymusgewicht als Stamm BSVS und reagierte mit einem signifikant hoheren Gewichtsanstieg der Milz. Der Anstieg des Thymusgewichtes war auf das Erscheinen unreifer, reticuloendothelialer Zellen zuruckzufuhren, wahrend zur Vergroserung der Milz eine Vermehrung der jugendlichen Granulocyten und unreifen Erythrocyten wesentlich beitrug, zusatzlich zur Vermehrung der reticuloendothelialen Zellen. 4. Serum- und Immunelektrophorese ergaben die Ausbildung eines hohen, kombinierten Beta- und Gammagipfels sowie eines hohen Alphagipfels an den Versuchstagen 7, 11 und 13. Wahrend die Erhohung des Gammaglobulingipfels bei Stamm BRVR rasch zuruckging, persistierte sie bei Stamm BSVS. 5. Es wird geschlossen, das zirkulierende Antikorper in dem vorliegenden Versuchsmodell keinen entscheidenden Einflus auf den Ausgang der Erkrankung besitzen.

The influence of different multiplicities of infection on the formation of infectious and transducing π1-phages was studied. The ratio of the two types of π1-phages formed is not the same. An agent is described which killed P. mirabilis bacteria without forming plaques. The synthesis of this agent is correlated with the formation of transducing phages, but not that of infectious phages. The possible identity of this agent with phage structures able to kill bacteria without plaque formation is discussed.

Aus den Bluten der rein weis bluhenden Mutante nivea vonAntirrhinum majus Sippe 50 wurden drei Phenolsubstanzen nachgewiesen. Diese drei Verbindungen konnten praparativ gewonnen werden. Sie erwiesen sich als Ester der Kaffee- und p-Cumarsaure. Durch eine abgewandelte Veresterungsmethode mit 4-Nitroazobenzol-4′-carbonsaurechlorid lies sich als alkoholische Komponente Chinasaure identifizieren. Die Ergebnisse wurden im Zusammenhang mit der Biosynthese der Flavonoide und Anthocyane diskutiert.

The influence of adsorption and multiplicities of infection on the transducing system Proteus mirabilis—π1 was studied. The frequency of transduction and the rate of survival depended on the duration of the incubation of the transducing mixture. The maximum of transducing frequency was obtained after 5 min of incubation at 37 °C. This time corresponds to that required for optimal adsorption. The frequency of transduction and the rate of survival depended on the multiplicities of infection. An optimal frequency of transduction for the system studied was obtained with multiplicities of infection ranging from 4:1 to 8:1.

1. Mutations toward streptomycin dependence occur in structural and functional heterogenous subunits of the streptomycin locus, which have been characterized as nonidentical alleles.str-d mutants of different, nonidentical alleles differ among themselves with respect to: a) the degree of depression of enzyme synthesis, the reaction toward sub-and superoptimal streptomycin concentrations, and their streptomycin and amino acid dependence, respectively, when grown in minimal medium; b) their allelespecific reaction with certain alleles of the genetic suppressorsu-str. They recombine among themselves with low frequency. 2. No specific subunits for thestr-d orstr-r mutation have been found within the complexstr-locus. It has been shown that a distinctstr-d allle may revert intraallelic to thestr-rd orstr-sd condition. In addition to intraallelic reversions, suppressor mutations cause streptomycin independence. 3. Thestr-d mutation is characterized by pleiotropic changes of the protein synthesis apparatus. It has been suggested that these changes affect the translation process and cause the dependence on streptomycin which acts as misreading inducing agent. 4. The function of streptomycin is allelespecific and represents a case of informational suppression. 5. The majority of streptomycin independent revertants is streptomycin-sensitive as the wild-type is. The major part of these revertants represent suppressor mutants genetically, and they are phenotypical either auxotrophic or noncompletely prototrophic. 6. Three groups of nonidentical suppressor alleles have been identified; between two of them (su-str A and-B) recombination occur with low frequency, while mutants of groupA orB recombine with mutants of groupsu-str C with higher frequency.A, B andC are thought to be components of one complex suppressor locussu-str. 7. The function of the suppressorsu-str is allelespecific, i.e. a certainsu-str allele either suppresses only distinctstr-d alleles or gives rise in combination with otherstr-d alleles to differences in the suppressor phenotype (auxotrophy or noncomplete prototrophy). 8. Auxotrophic and noncompletely prototrophic suppressor mutants differ in the effectivity of enzyme synthesis. These differences are interpreted as an expression of different degrees of compensation by the function of the suppressor of thestr-d allele induced misreading. Auxotrophy as well as noncomplete prototrophy are, therefore, integrated components or results of the allelespecific suppressor function. 9. The geneic suppressorsu-str has been characterized as an informational suppressor. 10. The suppressorsu-str interferes with the streptomycin indifference determining allelestr-r and with the allelesstr-s andstr-sd; in the first case the effect is a change in the degree of resistance, in the latter case, a depression of growth rate. 11. Suppressor mutants mutate with a generally high frequency to a limited streptomycin resistance. This change is caused by mutation of a modifier genemodstr. 12. Within the genome of suppressor mutants,modstr determines a limited streptomycin resistance; when being present in combination with the unsuppressedstr-d alleles,modstr acts in a similar way assu-str alleles; in the wild-type genomemodstr does not function as a resistance marker. These facts show that the function ofmodstr is genome specific. 13. It is supposed that the function ofmodstr like that ofsu-str is a result of a modification of certain ribosomal components.

Aspergillus flavus degradates progesterone in the same way as bacteria, but an alternative pathway leads through testololactone to a corresponding keto acid with the remaining lactone ring. At this stage of metabolism the lactone ring was enzymatically reconverted into the 5-ring ketone.

Measurements of UV sensitivity of wildtype cells (wt) and UV senistive mutants of E. coli and P. mirabilis suggest that the increased sensitivity of P. mirabilis (wt) is due either to incomplete repair of DNA lesions or to additive lethality probably as a result of UV induction of defective phage(s) present in P. mitabilis (Taubeneck, 1967). Direct estimates of the rate of pyrimidine dimer excision and a comparison of the UV reactivation capacity of E. coli and P. mirabilis for the temperate phages lambda and pi 1, respectively, support this conclusion.

The genes for ferredoxin from heterocysts (fdx H) and vegetative cells (pet F) of Anabaena sp. strain 7120 were subcloned into plasmid pUC 18/19. Both genes were expressed in Escherichia coli at high levels (≈10% of total protein). Pet F could be expressed from its own promoter. The ferredoxins were correctly assembled to the holoprotein. Heterocyst ferredoxin was purified from E. coli extracts on a large scale. Its biochemical and biophysical properties were identical to those of the authentic ferredoxin, isolated from Anabaena heterocysts.

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.

Summary Caffeine treatment of the virulent phage VIr ( Proteus mirabilis ) or of indicator bacteria inhibits host-cell reactivation of this phage after UV-irradiation or treatment with nitrogen mustard. No caffeine effect was observed with HCR-bacteria. Phages grown before treatment with UV or nitrogen mustard in the presence of caffeine were essentially as sensitive as those plated out on HCR + bacteria in the presence of caffeine. These results indicate that the inhibitioni of dark repair by caffeine is due to an interaction between DNA and caffeine. Inactivation of Proteus mirabilis by nitrogen mustard is much less affected by caffeine than inactivation by UV-irradiation. Evidently this effect is due to inhibition of the action of caffeine by nitrogen mustard since nitrogen mustard also causes a decreasein the efficiency of caffeine after UV-irradiation. These results are discussed with regard to the mechanisms of repair of damage caused by both UV-irradiation and nitrogen mustard.

Interaction between R-factor determined streptomycin (Sm) resistance (R-Sm) and chromosomally determined Sm dependence (str-d) has been studied using three different approaches by (i) attempts to transfer by conjugation the R-factor into Sm-dependent recipients, (ii) transduction of str-d alleles into R+ recipients, and (iii) investigation of Sm-dependent revertants of a suppressed Sm-dependent mutant harboring an R-factor. Evidence is presented which strongly suggests a lethal interference between the function of R-Sm genes and str-d allele determined Sm dependence in Proteus mirabilis.

The problem of selecting reference wavelengths appropriate for the study of reductive and oxidative absorbance changes in cytochromes b6 and ƒ is discussed. Action spectra for cytochrome b-563 photoreduction are consistent with this cytochrome functioning in a System I cyclic pathway, but do not exclude the possibility that the cytochrome might also have another function in a DCMU-sensitive pathway connected with Photosystem II. The dark oxidation of photoreduced cytochrome b-563 is inhibited by the quinone analog 2,5-dibromo-3-methyl-6-isopropylbenzoquinone (DBMIB), and restored by subsequent addition of plastoquinone. Diaminodurol causes a partial reduction of cytochrome b-563 in the dark. The photooxidation of diaminodurol-reduced cytochrome b-563 by System I is stimulated by addition of NH4Cl or ADP, and under the same conditions cytochrome ƒ becomes more reduced. The increase in the amplitude of cytochrome b-563 photooxidation caused by addition of NH4Cl is suppressed by the quinone analog DBMIB. The rate and amplitude of the photooxidation of dithionite-reduced cytochrome b6 are also stimulated by addition of NH4Cl, and this photooxidation is also inhibited by DBMIB. It is concluded that in the absence of added cofactors of cyclic electron transport the pathway of cytochrome b-563 oxidation includes plastoquinone and the coupling site between plastoquinone and cytochrome ƒ. In the presence of DBMIB, phenazine methosulfate (PMS) restores the dark oxidation of photoreduced cytochrome b-563 and also causes a decrease in the amplitude of cytochrome ƒ photooxidation. When DCMU is substituted for DBMIB, PMS has no effect on the amplitude of cytochrome ƒ photooxidation. It is concluded that in cyclic phosphorylation one function of PMS is to transfer electrons from cytochrome b6 to System I either through the plastoquinone-cytochrome ƒ coupling site or in the presence of DBMIB through a bypass of this site.