Die Serumgruppen-Systeme Lp(a), Gm(a), Gc und Hp bei Cerebralsklerotikern

Zusammenfassung Im genetisch determinierten Lp(a)-System war die Häufigkeit von Lp(a+) bei 307 Cerebralsklerosefällen statistisch signifikant erhöht im Vergleich zur Lp(a+)-Häufigkeit der gleichen Population. In den Systemen Gm(a), Gc und Hp wurde dagegen keine Veränderung der Genotypenhäufigkeit infolge der arteriosklerotischen Erkrankung festgestellt.

---

In the genetically determined Lp(a) system the frequency of Lp(a+) showed with 45.6 per cent a statistically significant raise in 307 patients with cerebral sclerosis compared with 38.7 per cent in normal population. The increase of Lp(a+) is almost exclusively confined to weakly positive precipitation and is discussed in connection with the often observed increase of -lipoprotein concentration in the serum of arteriosclerotic persons. As expected no changes of genotype frequency due to arteriosclerotic diseases has been stated in the Gm(a), Gc and Hp system.

---

---

Herrn Medizinalrat Dr. Wieder, Ärztlicher Direktor des Bezirkskrankenhauses, sind wir für die Überlassung der Blutproben zu besonderem Dank verpflichtet.

---

(Direktor: Obermedizinalrat Dr. med. K. Thomas)     

Human-type blood groups and Gm factors in gibbons (Hylobates)

Blood specimens from 69 gibbons (63Hylobates lar, 4Hylobates concolor, and 2Hylobates pileatus) were tested for human-type ABO, MN, and Rh blood groups. AmongH. lar, three phenotypes were noted in the ABO and MN blood groups respectively, but all fourH. concolor were grouped as AM. All group A gibbons were of subgroup A₁; subgroups A₂B and A₁₂B were observed at a low frequency in group AB gibbons. Le^b antigen was detected in about 30% of the red cell samples fromH. lar, but all the samples were negative for Le^a. All the gibbons tested had c(hr) antigen but no other Rh antigens (D, C, E, and e) in their red cells. Some selected blood samples fromH. lar were also tested for some other blood group antigens and for the Gm and Inv factors. The Jk^a antigen was detected in all the red cell samples tested, but the S, s, U, K, k, and Fy^a antigens were not. In the tests of plasma with anti-Gm (1),H. lar could be divided into two groups, i.e., Gm(1)^Gi and Gm(–1)^Gi; Gm(2), Gm(4), and Inv(1) were absent in the species.     

Cytogenetische,immunologische und cytologische Familienuntersuchungen bei Bloom-Syndrom

Zusammenfassung Das Bloom-Syndrom gehört mit der Fanconi-Anämie und der Ataxia-Telangiektasia Louis-Bar zu einer Gruppe von Anomalien, die als gemeinsame Kennzeichen eine autosomal-recessive Vererbung, gehäufte spontane strukturelle Chromosomenaberrationen und ein erhöhtes Risiko für die Entstehung maligner Neoplasien haben. Bei 2 eigenen Patienten fanden wir gehäufte strukturelle Chromosomenanomalien—Brüche, Fragmente und Translokationsfiguren—in kultivierten Lymphocyten, während Fibroblastenuntersuchungen wegen nur mangelhafter Proliferation der Kulturen mißlangen. Entsprechende Chromosomenaberrationen konnten gehäuft auch in Lymphocyten und Fibroblasten vom Vater des Jungen, nicht aber bei beiden Müttern nachgewiesen werden. Der Patient hat einen Immunglobulinmangel in den drei Fraktionen a, g und m, das Mädchen nur ein a-Defizit. Die Immunglobuline des Vaters und der Mütter sind normal. Auf PHA reagieren die Lymphocyten der Patienten und der untersuchten Eltern mit normaler Transformations-und Proliferationsrate, wenn auch die Mehrzahl der Kulturen des Jungen und mehrere Kulturen seiner Eltern—vielleicht infolge größerer Empfindlichkeit gegen exogene Störfaktoren—mißlangen.

---

Cytogenetic, immunological, and cytological studies on two families with Bloom's Syndrome

Summary Autosomal recessive inheritance, increased incidence of structural chromosomal anomalies, and high risk for malignancies are common features of Bloom's syndrome, Fanconi's anemia, and Louis-Bar's ataxia-telangiectasia. A high fequency of structural chromosomal aberrations—breaks, fragments, and translocation figures—was found in lymphocytes of 2 patients with Bloom's syndrome whereas studies on fibroblasts could not be done because of poor proliferation. An increased rate of chromosome aberrations was also seen in lymphocytes and fibroblasts of the boy's father but not in the cells of both mothers. a, g, and m were deficient in the boy. The girl had only a a deficiency, and the parents' immunoglobulins were normal. The lymphocytes of both patients and parents responded normally to PHA, but several cultures of the boy's parents and 5 out of 7 cultures from the boy failed to respond, maybe because of pronounced susceptibility to exogenous disturbance.

---

---

Mit dankenswerter Unterstützung durch die Deutsche Forschungsgemeinschaft (Ke 128/1).     

Displacement of excitatory amino acid receptor ligands by acidic oligopeptides

A number ofD-glutamyl andL-aspartyl dipeptides, glutathione, -D-glutamylglycine and -D-glutamyltaurine, were tested for their efficacy to displace ligands specific for different subtypes of excitatory amino acid receptors from rat brain synaptic membranes. In general, theL enanthiomorphs of -glutamyl peptides were more potent displacers than -D-glutamylglycine and-taurine but the latter were more specific for the quisqualate type of receptors. -L-glutamyl-L-glutamate was the most effective dipeptide in displacing the binding of glutamate, 2-amino-3-hydroxy-5-methylisoxazole-4-proprionate (AMPA) and 2-amino-5-phosphonoheptanoate (APH), whereas -L-glutamyl-L-aspartate was the most effective in the binding of kainate. Both oxidized and reduced glutathione were inhibitory, being most potent in the binding of AMPA. -L-Glutamylaminomethylsulphonate was most effective in the binding of APH. The most potent -L-glutamyl peptides (glutathione, -L-glutamyl-L-glutamate,-L-aspartate, and-glycine) may act as endogenous modulators of excitatory aminoacidergic neurotransmission.     

Hämatologische beobachtungen an regenbogenforellen (Salmo gairdneriRich.) VII. Färbeindex (FI), absoluter Hämoglobingehalt des Einzelerytrozyten (HbE) and mittlere Hämoglobinkonzentration des Einzelerythrozyten (MCHC)

180 rainbow trouts (Salmo gairdneriRich.), aged from 1 to 3 years, were examined for fluctuations, caused by age and season, by means of colour index (CI), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC).CI and MCH behave similarly. Both are increasing until the 2nd year and stay relatively constant thereafter. If the gender is not considered — there are no significant differences in the values of males and females — the CI increases from 1,4 in the first year over 1,6 to 1,7 in the age of 3 years, and the MCH increases from 44,4 over 52,6 , 56,8 , 58,1 to 55,5 .A seasonal periodicity of both indices could not be indicated on not-matured animals (F₂) which were two summers of age. Only, the january values appeared increased — CI: 2, MCH: 68,3 — otherwise the CI varies between 1,8 and 1,7 and the MCH between 53,3 and 59,1 .The MCHC-values of the age groups examined vary between 24,4% and 27,3%. The values of the yearlings form an exception (19,8%). These values certainly are inexact and too low because of the small number of individuals checked (3).

---

---

Mit finanzieller Unterstützung durch die DFG.Institut für Siedlungswasserbau und Wassergütewirtschaft der Universitat Stuttgart Fischtoxikologische Arbeitsgruppe     

Solubilization and some properties of γ-glutamyltransferase from human brain microvessels

Detergents Triton X-100, sodium deoxycholate, and octyl--D-glucopyranoside, and proteinase papain proved to be excellent agents solubilizing the -glutamyl-transferase (-GT) from human brain cortex microvessels. Ficin also solubilized -GT but to a lesser extent than papain. The relative molecular mass of the detergent-solubilized enzyme form was greater than 200,000 (in the presence of Triton X-100). The relative molecular mass of the proteinase-solubilized form was slightly greater than that of albumine. -GTs of microvessels from five human brain regions and from the choroid plexus were tested for their specificity toward acceptors. The best acceptors were found to be (in decreasing order of activity)l-cystine, glycylglycine,l-glutamine,l-methionine, andl-alanine. The findings suggest that the main features of -GT of the human blood-brain barrier are very similar to those of -GTs from other human tissues.     

Assimilation of γ-butyrobetaine,and d-and l-carnitine by resting cell suspensions of Acinetobacter calcoaceticus and Pseudomonas putida

The metabolic pattern of utilization of [1,2,3,4-¹⁴C, methyl-³H] -butyrobetaine and d-and l-[1-¹⁴C, methyl-³H]carnitine has been examined with variously grown resting cell suspensions of Acinetobacter calcoaceticus and Pseudomonas putida. Ps. putida grown on d, l-carnitine as the sole source of carbon, degraded only l-carnitine with stoichiometric accumulation of glycinebetaine. Alternatively, when grown on -butyrobetaine, Ps. putida rapidly metabolized -butyrobetaine, and to a lesser but significant extent, both d-and l-carnitine with equivalent formation of trimethylamine and degradation of the betaine carbon skeleton. Ac. calcoaceticus grown on either d,l-carnitine or -butyrobetaine, effectively utilized all three betaines at nearly the same rates. Disappearance of each of these quarternary ammonium compounds was accompanied by stoichiometric formation of trimethylamine and degradation of the carbon backbone. Utilization of the betaines and corresponding formation of trimethylamine by resting cell suspensions of appropriately grown Ac. calcoaceticus and Ps. putida, was essentially abolished under conditions of anaerobiosis and severely impaired in the presence of sodium cyanide, sodium azide, 2,4-dinitrophenol or 2,2-bipyridine. The results of the present investigations with resting cell suspensions of both Ac. calcoaceticus and Ps. putida do not support an earlier suggestion that -butyrobetaine degradation in these organisms proceeds by its prior hydroxylation to l-carnitine. Indeed, disrupted cell-free preparations of Ac. calcoaceticus and Ps. putida grown on either d,l-carnitine or -butyrobetaine showed no detectable -butyrobetaine hydroxylase activity.     

The ethnological significance of the gamma-globulin (Gm) factors in melanesia

A study was made of the distribution of the immunoglobulin markers Gm(a), (x), (z), (f), (g), (b⁰), (b¹), (b³), (s), (t), (c³), (c⁵) and Inv (1) and Inv (a) in 906 individuals sampled from several population groups living in various parts of New Guinea and New Britain. A study of 123 families confirmed the presence of the following gene complexes: Gm^za;g, Gm^zax;g, Gm^za;b and Gm^fa;b. Gm(s), (t), (c³) and (c⁵) were absent and either all or none of Gm(b⁰), (b¹) and (b³) present. Striking differences occurred in the geographical and ethnic distribution of the Gm gene complexes. Gm^fa;g was either absent or in very low frequency, and Gm^za;b, Gm^zax;g and Gm^za;g were present in varying frequencies in both the highland and western coastal populations in the mainland of New Guinea. All of these populations spoke non-Austronesian languages. On the other hand Gm^fa;b was present in the Melanesian-speaking Motu of the Central District of the mainland, in the Melanesian-speaking Tolai and the non-Austronesian-speaking Sulka and Baining of the island of New Britain. It is suggested that Gm^fa;b and Gm^za;b are respectively Malayo-Polynesian and pre-Austronesian markers, although a clear cut distinction between modern populations derived from these stocks is often blurred by the effects of gene flow and drift. Considerable ethnic and geographical variation was also found in the distribution of Inv(1) and Inv(a). In two Highland NAN-speaking populations the Inv(1⁺a⁺) phenotype percentages were 1.0 and 5.4, whilst percentages ranging from 0.0 to 56.4% were found for coastal MN-speaking populations. The percentages of Inv(1⁺a⁺) in the total MN- and NAN-speaking populations were 31.6 and 10.0 respectively.     

Effect of anticancer drugs on the release of interleukin-6 in vitro

Summary This study investigates the effects of anticancer drugs and immunomodulating agents on the release of interleukin-6 (IL-6) from lipopolysaccharide-stimulated human peripheral blood mononuclear leucocytes in vitro. The addition of non-cytotoxic concentrations of Adriamycin (doxorubicin), vincristine and 4-OOH-cyclophosphamide (the in vitro active analogue of cyclophosphamide) resulted in suppression of IL-6 release. The drugs bleomycin, FK156 [d-lactoyl-l-alanyl--d-glutamyl-(l)-meso-diaminopimelyl-(l)-glycine], FK565 [heptanoyl--d-glutamyl-(l)-meso-diaminopimelyl-(d)-alanine] and the immunosuppressive agent cyclosporin A did not alter the release of IL-6 in the same experimental system.     

Chimeric B72.3 mouse/human (IgG1) antibody directs the lysis of tumor cells by lymphokine-activated killer cells

Summary Chimeric mouse/human B72.3 (cB72.3) antibodies having a human IgG1 (1) or IgG4 (4) constant region were compared to the native murine IgG1 B72.3 (nB72.3) monoclonal antibody (mAb) for their ability to participate with human effector cells in antibody-dependent cellular cytotoxicity (ADCC). Because the TAG-72 antigen recognized by B72.3 is poorly expressed on tissuecultured tumor cell lines, the xenografted OVCAR-3 human ovarian carcinoma ascites was used as a cytotoxicity target. The lytic activity of the cB72.3(1) mAb with peripheral blood lymphocytes was 1.5- to 50-fold greater than that of the nB72.3 mAb and usually the cB72.3(4) mAb. However, lymphocytes from some donors had similar ADCC activity with either the cB72.3(1) or cB72.3(4) mAb. The cB72.3(1) and the murine anti-colon carcinoma CO17-1A mAb had comparable activity in mediating ADCC against the OVCAR-3 tumor. Exposure of lymphoid cells to interleukin-2 (IL-2) (100–500 U/ml) for 24 h to generate lymphokine-activated killer (LAK) cells augmented ADCC mediated by the cB72.3(1) mAb 2- to 22-fold. By contrast, LAK cells from most donors expressed weak non-specific cytotoxicity against OVCAR-3 ascites tumor cells. The cB72.3(1), and to a lesser extent, the cB72.3(4) chimera also participated with monocytes in mediating ADCC, but the antibody-dependent lytic potency of monocytic effectors was much weaker than that of IL-2-activated lymphoid cells. These studies show that the cB72.3(1) mAb has appreciable ADCC-mediating properties, suggesting a potential role for its incorporation into treatment strategies utilizing adoptive killer cell and/or lymphokine therapy. Offprint requests to: J. Schlom, to whom reprint requests should be sent at 9000 Rockville Pike, Building 10, Room 8B07, Bethesda, MD 20892, USA     

Modulation of the serotonin-activated K+ channel by G protein subunits and nucleotides in rat hippocampal neurons

In hippocampal neurons, 5-hydroxytryptamine (5-HT) activates an inwardly rectifying K⁺ current via G protein. We identified the K⁺ channel activated by 5-HT (K_5-HT channel) and studied the effects of G protein subunits and nucleotides on the K⁺ channel kinetics in adult rat hippocampal neurons. In inside-out patches with 10 m 5-HT in the pipette, application of GTP (100 m) to the cytoplasmic side of the membrane activated an inwardly rectifying K⁺ channel with a slope conductance of 36±1 pS (symmetrical 140 mm K⁺) at –60 mV and a mean open time of 1.1±0.1 msec (n=5). Transducin activated the (K_5-HT) channels and this was reversed by -GDP. Whether the K_5-HT channel was activated endogenously (GTP, GTPS) or exogenously (), the presence of 1 mm ATP resulted in a 4-fold increase in channel activity due in large part to the prolongation of the open time duration. These effects of ATP were irreversible and not mimicked by AMPPMP, suggesting that phosphorylation might be involved. However, inhibitors of protein kinases A and C (H-7, staurosporine) and tyrosine kinase (tyrphostin 25) failed to block the effect of ATP. These results show that G activates the G protein-gated K⁺ channel in hippocampal neurons, and that ATP modifies the gating kinetics of the channel, resulting in increased open probability via as yet unknown pathways.     

Interactions of γ-L-glutamyltaurine with excitatory aminoacidergic neurotransmission

The in vitro effects of -L-glutamyltaurine on different stages of excitatory aminoacidergic neurotransmission were tested with -D-glutamyltaurine as reference. -L-Glutamyltaurine enhanced the K⁺-stimulated release of [³H]glutamate from cerebral cortical slices (25% at 0.1 mM) and slightly inhibited the uptake by crude brain synaptosomal preparations (about 10% at 1 mM). -L-Glutamyltaurine was also a weak displacer of glutamate and its agonists from their binding sites in brain synaptic membrane preparations, being, however, less selective to quisqualate (QA) sites than -D-glutamyltaurine. The basal influx of Ca²⁺ into cultured cerebellar granular cells was not affected by 1 mM -L-glutamyltaurine, but the glutamate- and its agonist-activated influx was significantly inhibited in low-Mg²⁺ (0.1 mM) and Mg²⁺-free media. The glutamate-evoked increase in free intracellular Ca²⁺ and the kainate-activated formation of cGMP in cerebellar slices were both markedly inhibited by 0.1 mM -L-giutamyltaurine. We propose that -L-glutamyltaurine may act as endogenous modulator in excitatory aminoacidergic neurotransmission.     

Hydrolysis ofγ-glutamyl linkages byFusobacterium nucleatum

The cell extracts of two human oral strains (FN2 and FN3) ofFusobacterium nucleatum displayed exceptionally high-glutamylpeptidase activity as determined withN--l-glutamyl-2-naphthylamine as substrate. This activity was so dominant that the hydrolysis of otherN-aminoacyl-2-naphthylamines progressed at a rate <10% of the former. Two major enzymes (I and II) were partially purified from FN2. I had a molecular weight of 115,000 and did not hydrolyze-glutamylcysteinylglycine (glutathione). II had a molecular weight of 70,000 and rapidly liberated only glutamic acid from glutathione. Strain FN3 contained several enzymes hydrolyzing-glu-2NA. Direct anion exchange chromatography of FN3 cell extracts separated one enzyme that liberated both glutamic acid and glycine from glutathione, one that was inactive against glutathione (but hydrolyzed-glu-2NA), and one that liberated only glutamic acid. Although-glu-2NA was a good synthetic substrate, glutathione was hydrolyzed at least 500 times faster by an enzyme present in both strains. These results indicate that the presence of-glutamylpeptidase activity is very characteristic of theseF. nucleatum strains.     

Probing the structure of the core light-harvesting complex (LH1) of Rhodopseudomonas viridis by dissociation and reconstitution methodology

A subunit complex was formed from the core light-harvesting complex (LH1) of bacteriochlorophyll(BChl)-b-containing Rhodopseudomonas viridis. The addition of octyl glucoside to a carotenoid-depleted Rps. viridis membrane preparation resulted in a subunit complex absorbing at 895 nm, which could be quantitatively dissociated to free BChl b and then reassociated to the subunit. When carotenoid was added back, the subunit could be reassociated to LH1 with a 25% yield. Additionally, the Rps. viridis - and -polypeptides were isolated, purified, and then reconstituted with BChl b. They formed a subunit absorbing near 895 nm, similar to the subunit formed by titration of the carotenoid depleted membrane, but did not form an LH1-type complex at 1015 nm. The same results were obtained with the -polypeptide alone and BChl b. Isolated polypeptides were also tested for their interaction with BChl a. They formed subunit and LH1-type complexes similar to those formed using polypeptides isolated from BChl-a-containing bacteria but displayed 6–10 nm smaller red shifts in their long-wavelength absorption maxima. Thus, the larger red shift of BChl-b-containing Rps. viridis is not attributable solely to the protein structure. The -polypeptide of Rps. viridis differed from the other -polypeptides tested in that it could form an LH1-type complex with BChl a in the absence of the - and -polypeptides. It apparently contains the necessary information required to assemble into an LH1-type complex. When the -polypeptide was tested in reconstitution with BChl a and BChl b with the - and -polypeptides, it had no effect; its role remains undetermined.Abbreviations B820 the subunit form of the core light-harvesting complex in BChl-a-containing bacteria which has an absorption maximum at or near 820 nm - B875 the core light-harvesting complex of Rhodobacter sphaeroides which has an absorption maximum at 875 nm - B881 the core light-harvesting complex of wild-type Rhodospirillum rubrum which has an absorption maximum at 881 nm - B895 the subunit form of the core light-harvesting complex in Rps. viridis which has an absorption maximum near 888–895 nm - B1015 the core light-harvesting complex of Rps. viridis which has an absorption maximum at 1015 nm - CD circular dichroism - LH1 the core light-harvesting complex - OG n-octyl -d-glucopyranoside     

Cyclic hexapeptide antagonists of the bradykinin B2 receptor: Receptor binding and solution backbone conformation

Summary Cyclic hexapeptide analogs of bradykinin, based on a folded receptor-bound model of bradykinin, were found to be able to antagonize the action of bradykinin at its B₂ bradykinin receptor. The best of these, cyclo(d-Lys(Arg)-Phe-Ser-d-Tic-Oic- Arg) [compound 17], has affinities at the human and rat B₂ bradykinin receptors of 230 and 8.5 nM, respectively. This potency is significant, since the analogs lack the C-terminal carboxylate group, residues 2–4 and the important interaction of Phe⁵. These constrained analogs may serve as tools for the determination of the receptor-bound conformation of antagonists at the bradykinin receptor and for the design of even smaller and more potent antagonist analogs.Abbreviations Arg(Me) N-methyl-l-arginine - Arg(Me)₂ N,N-dimethyl-l-arginine - Boc t-butoxycarbonyl - Oic (S,S,S)-octahydroindole-2-carboxylic acid - PAM phenylacetamidomethyl - PyBOP benzotriazole-l-yl-oxy-tris-pyrrolidino-phosphonium hexafluorophosphate - Thi -(2-thienyl)-l-alanine - Tic l-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid     

γ-Linolenic acid production from Spirulina platensis

Various Spirulina strains were assayed for their productivity of -linolenic acid (Lnn). Spirulina platensis ARM-346 was found to accumulate large amounts of Lnn. Urea as a nitrogen source was found to be most effective giving a yield of 13.5 mg Lnn/g dry cell mass. With increase in temperature the Lnn content was found to increase along with biomass. The optimum temperature for maximum Lnn and biomass production was found to be 35°C. The Lnn content was highest at 0.06% (w/v) NaCl and 0.07% (w/v) K₂HPO₄. Cells cultivated in the orange region of the electromagnetic spectrum as energy source showed a high content of Lnn, and there was less biomass compared to cells grown in red light. When the culture was left in the dark for various times, after 144 h it contained about 26% more Lnn than in conventionally cultivated cells.     

Beziehungen zwischen Carnitinstoffwechsel und Fettsäureassimilation bei Pseudomonas putida

Zusammenfassung Der Carnitinstoffwechsel und einige Beziehungen zum Fettsäurestoffwechsel wurden mittels der Wachstumskontrolle, der Bestimmung von Metaboliten und des Nachweises von Enzymaktivitäten in Pseudomonas putida untersucht. Der Stamm wuchs auf -Butyrobetain, D,L-und L-Carnitin, Glycinbetain, Cholin, D,L-Norcarnitin, D,L--Amino--hydroxybutyrat und D,L--Hydroxybutyrat. Obwohl der Stamm unverzweigte Fettsäuren von 2–16 C-Atomen zu untzen vermag, konnte er nur auf O-Acyl-L-carnitinen von 10 oder mehr C-Atomen in der Acylgruppe wachsen. Zugabe von Carnitin stimulierte das Wachstum auf langkettigen Fettsäuren.Die Bildung von Trimethylamin stieg, wenn Carnitin oder -Butyrobetain nur C-Quellen waren, und sank, wenn diese Trimethylammoniumverbindungen sowohl C-als auch N-Quellen waren. L-Carnitin induzierte sowohl die Carnitindehydrogenase als auch die -Hydroxybutyratdehydrogenase. -Butyrobetain als C-und N-Quelle induzierte ebenfalls die Carnitindehydrogenase. Im Rohextrakt betrug die spezifische Aktivität der -Hydroxybutyratdehydrogenase entsprechend dem Wachstum auf L-Carnitin oder D,L--Hydroxybutyrat 0,7 oder 1,6 Mol · min^-1 · mg^-1. Glycinbetain, Glucose und langkettige Fettsäuren reprimierten die Synthese beider Enzyme. Abhängig von der N-Quelle wird L-Carnitin offensichtlich auf zwei unterschiedlichen Stoffwechselwegen abgebaut.

---

Interrelationships between carnitine metabolism and fatty acid assimilation in Pseudomonas putida

The carnitine metabolism and some relations to the fatty acid metabolism were studied in Pseudomonas putida by means of control of growth, analysis of metabolites, and determination of enzyme activities. The strain grew on -butyrobetaine, D,L-and L-carnitine, glycinebetaine, choline, D,L-norcarnitine, D,L--amino--hydroxybutyrate, and D,L--hydroxybutyrate. Although the strain used straight-chain fatty acids of 2–16 C-atoms, it was only able to grow on O-acyl-L-carnitines of 10 or more C-atoms in the acylgroup. Addition of carnitine stimulated the growth on long-chain fatty acids.The formation of trimethylamine increased, if L-carnitine or -butyrobetaine were the only carbon sources, and decreased, if these trimethylammonium compounds were carbon as well as nitrogen sources. L-Carnitine induced the carnitine dehydrogenase as well as the -hydroxybutyrate dehydrogenase. -Butyrobetaine as carbon and nitrogen source induced the carnitine dehydrogenase, too. In the crude extract the specific activities of -hydroxybutyrate dehydrogenase were 0.7 or 1.6 moles·min^-1·mg^-1 after growth on L-carnitine and D,L--hydroxybutyrate, respectively. The synthesis of both enzymes was repressed by glycinebetaine, glucose and long-chain fatty acids. Dependent on the nitrogen source L-carnitine was catabolized via two different pathways.

     

Die campaniformen Sensillen im Pedicellus der Florfliege (Chrysopa,Planipennia)

Zusammenfassung Der Pedicellus der Florfliege (Chrysopa) enthält an seinem Distalende fünf campaniforme Sensillen. Sie bestehen aus vier Zellen: einer Sinneszelle, einer trichogenen Zelle (= accessory supporting cell Stuart u. Satir, 1968) und zwei Hüllzellen. Im rezeptorischen Fortsatz der Sinneszelle wurzelt ein umgewandeltes Cilium, dessen Distalende von einer cuticularen Scheide umhüllt wird.

---

On the campaniform sensilla of the pedicel of Chrysopa

Summary At the apex of the pedicel in Chrysopa there are five campaniform sensilla, which are arranged in a cycle. They are composed of four cells: two enveloping cells, a trichogen cell (= accessory supporting cell, Stuart and Satir, 1968) and one sense cell. The distal nerve process contains a transformed cilium. The tip of the cilium with the so called tubular body is enveloped by a cuticular sheath.

---

---

Die Untersuchung wurde mit Unterstützung durch die Deutsche Forschungsgemeinschaft durchgeführt.     

Potassium-39 NMR of K+ interaction with the gramicidin channel and NMR-derived conductance ratios for Na+, K+ and Rb+

Summary A potassium-39 NMR study of potassium ion interaction with the gramicidin transmembrane channel in phospholipid bilayers at high ion activity is reported which allows determination of a weak binding constant, K _b ^w 8.3/m, and an off-rate constant for the weak site,k _off ^w 2.6×10⁷/sec. These values are interpreted with the aid of additional NMR data as the binding constant for formation of the doubly occupied channel state and the rate constant for an ion leaving the doubly occupied state. Considering the singly occupied channel state for the potassium ion to be electrically silent at 1 molar ion activity, as with the sodium ion, the single-channel conductance for 100 mV and 30°C calculated to be 29 pS, and using the same approximation with previous NMR results on the sodium and rubidium ions, reasonable conductance ratios were calculated. Further experimental estimates of the other three constants with the experimental location of binding sites and Eyring rate theory to introduce voltage dependence allowed a more complete calculation of the two-site channel. The single-channel conductance for potassium ion is calculated to be 24 pS at 1m activity and 26 pS at 0.6m activity, which compares for diphytanoyl phosphatidylcholine membranes to an experimental most probable single-channel conductance of 25 pS and a mean channel conductance of 20 pS. The calculated conductance ratios using NMR-derived constants were (K)/(Na)=2.0 and (Rb)/(Na)=4.3. These results are close to the experimental values and provide further basis for the use of NMR of quadrupolar ions to provide information on the ionic mechanism of channel transport.     

Expression and regulation of Q8 b in a transfected cell line

RNase protection experiments showed that Q8 ^b was actively transcribed in a stably transfected cell line. Moreover, Q8 ^b responded to interferon- (IFN-) treatment with increased levels of mRNA expression. Thus Q8 ^b demonstrates a regulatory response to IFN- characteristic of many other class I genes. Cell surface expression of a Q8^b product could also be detected by flow cytometric analysis with the Qa-2-specific monoclonal antibody D3.262. The expression of the Q8^b cell surface product increased only slightly after cells were treated with IFN-. The Q8^b cell surface product was not sensitive to cleavage by phosphatidylinositol-phospholipase C. These results suggest that the Q8^b product, unlike the predominant forms of Qa-2-bearing molecules, is not anchored via phosphatidylinositol to the cell membrane. These results also suggest that Q8 ^b has the potential to contribute to the Qa-2 phenotype in vivo. Address correspondence and offprint requests to: L. Flaherty.