Isolation,structure determination and biological activity of A-16686 factors A′ 1, A′ 2 and A′ 3 glycolipodepsipeptide antibiotics

Summary WhenActinoplanes strain ATCC 33076, the producer of A-16686 A1, A2 and A3 complex, is fermented in a suitable medium three additional factors, designated A1, A2 and A3 are produced. These were isolated and characterized, and were shown to differ from the parent components of the original complex by lacking one mannose unit. Bioconversion of A factors into A factors was achieved by incubation with the mycelium ofActinoplanes ATCC 33076. Factor A2 has better antibacterial activity than A2 against some bacteria.     

Degradation of the diarylpropane lignin model compound 1-(3′,4′-diethoxyphenyl)-1,3-dihydroxy-2-(4′'-methoxyphenyl)-propane and derivatives by the basidiomycete Phanerochaete chrysosporium

The white rot basidiomycete Phanerochaete chrysosporium metabolized 1-(3,4-diethoxyphenyl)-1,3(dihydroxy)-2-(4'-methoxyphenyl)-propane (XII) in low nitrogen stationary cultures, conditions under which the ligninolytic enzyme system is expressed. 3,4-Diethoxybenzyl alcohol (IV), 1,2(dihydroxy)-1-(4-methoxyphenyl)ethane (XX) and anisyl alcohol were isolated as metabolic products indicating an initial , bond cleavage of this dimer. Exogenously added XX was rapidly converted to anisyl alcohol, indicating that XX is an intermediate in the metabolism of XII. Fungal cleavage of the , bond of 1-(3-4-diethoxyphenyl)-1-(hydroxy)-2-(4'-methoxyphenyl)ethane (XI) also occurred, indicating that a hydroxymethyl group is not a prerequisite for this reaction. P. chrysosporium also metabolized 1-(4-ethoxy-3-methoxyphenyl)-2,2(dihydroxy)-2-(4'-methoxyphenyl)propane-1-ol (XIII). The major products of the degradation of this triol included 4-ethoxy-3-methoxybenzyl alcohol (III) and 2-hydroxy-1-(4-methoxyphenyl)-1-oxoethane (XXI). The nature of the products formed indicates that this triol is also cleaved directly at the , bond. The significant difference in the nature of the products formed from the diaryl propane (XII) and the triol (XIII), however, suggests that XIII is not an intermediate in the major pathway for the degradation of XII. Metabolites were identified after comparison with chemically synthesized standards by GLC-mass spectrometry.Abbreviations GLC Gas liquid chromatography - TMSi trimethylsilyl - TLC thin layer chromatography - MS mass spectrometry     

Inactivation of DNA polymerases by adenosine 2′,3′-riboepoxide 5′-triphosphate allows estimation of the primers affinity

Template-primer dependent inactivation of human DNA polymerase and Klenow fragment of E. coli DNA polymerase I by adenosine 2,3-riboepoxide 5-triphosphate was used for quantitative analysis of the K_d values for oligonucleotide primers of different length. The K_d values are smaller by a factor of 2.5 than the K_m values for the same primers determined in the reaction of DNA polymerization in the case of DNA polymerase . The K_d and K_m values are nearly the same for Klenow fragment. Such approach to the determination of K_m/K_d ratio can likely be used for detailed quantitative analysis of DNA polymerases.Abbreviations epATP adenosine 2,3-riboepoxide 5-triphosphate - KF Klenow fragment of E. coli DNA polymerase I - Pol I E. coli DNA polymerase I - Pol human placenta DNA polymerase      

2′(3′),5′-ADP inhibits initiation-dependent protein synthesis in a cell-free system from Ehrlich ascites tumor cells

When tested in a poly(U)-dependent polyphenylalanine synthesizing system and in a postnuclear supernatant, both derived from Ehrlich ascites tumor cells, 2(3),5-ADP did not affect chain elongation of polypeptide synthesis. In a cell-free system which was dependent on initiation and programmed by natural mRNA, however, the amino acid incorporating activity was suppressed to about 10% of the control in the presence of 1 mM 2(3),5-ADP. The inhibitor was shown not to interfere with the attachment of poly(U) to the small ribosomal subunit and with the formation of mRNA-80S ribosome complexes in a complete protein synthesizing system. The subsequent attachment of a 40S ribosomal subunit to the mRNA-80S ribosome complex and the formation of polysomes, however, was depressed by the inhibitor. The experimental results suggest that 2(3),5-ADP inhibits initiation-dependent protein synthesis between monosome formation and the formation of the first peptide bond(s).     

Non-coordinate synthesis of RNA polymerase beta beta'' subunits in a temperature-sensitive beta''-subunit mutant of Escherichia coli

Summary On exposure to high temperature of a temperature-sensitive RNA polymerase subunit (rpoC92) mutant of Escherichia coli, selective reduction was observed in the rate of synthesis of a group of proteins including RNA polymerase subunit. The finding that the synthesis of subunit but not subunit was specifically repressed in this mutant grown at non-permissive temperature indicates that the functionally intact RNA polymerase is required for the synthesis of subunits be coordinated. In addition, the assembly of newly synthesized RNA polymerase subunits was inefficient in this mutant at the steps where altered subunit was involved, and the unassembled enzyme subunits were rapidly and preferentially degraded. During recovery to non-restricted growth, the synthesis of both and subunits was transiently enhanced in parallel leading to recovery of the intracellular concentration of functional RNA polymerase.     

Full 1H NMR assignment of a 24-nucleotide RNA hairpin: Application of the 1H 3D-NOE/2QC experiment

The subject RNA models the binding site for the coat protein of the R17 virus, as well as the ribosome recognition sequence for the R17 replicase gene. With an RNA of this size, overlaps among the sugar protons complicate assignments of the ¹H NMR spectrum. The cross peaks that overlap significantly in 2D-NOE spectra can frequently be resolved by introducing a third, in our approach the double-quantum, frequency axis. In particular the planes in a 3D-NOE/2QC spectrum perpendicular to the 2Q axis are extremely useful, showing a highly informative repeating NOE-2Q pattern. In this experiment substantial J-coupling confers special advantages. This always occurs for geminal pairs (H5/H5 for RNA plus H2/H2 for DNA), as well as for H5/H6, for H3/H4 in sugars with substantial populations of the N-pucker, for H1/H2 for S-puckered sugars, and usually for H2/H3. For the 24-mer RNA hairpin the additional information from the 3D-NOE/2QC spectrum allowed assignment of all of the non-exchangeable protons, eliminating the need for stable-isotope labeling.     

Cajaflavanone and cajanone released from Cajanus cajan (L. Millsp.) roots induce nod genes of Bradyrhizobium sp.

A broad-host-range plasmid (pEA2-21) containing a Bradyrhizobium sp (F-4) nod DABC-lacZ translation fusion was constructed and used to monitor nod gene expression in response to pigeonpea root exudate. Two nod-inducing compounds were isolated and identified. Spectral analysis using ultraviolet absorption, infrared spectra, proton nuclear magnetic resonance, and mass spectrometry showed that the two inducers were 5,4-dihydroxy-6-(3-methyl-2-butenyl)-2, 2-dimethyl pyrano-[5, 6:7, 8]-flavanone (cajaflavanone) and 2,4,5-trihydroxy-5-isopentenyl-6, 7-dimethylchromene iso-flavanone (cajanone). When pEA2-21 was introduced into Rhizobium trifolii and R. meliloti cajanone and cajaflavanone did not induce nod gene indicating that specificity of induction appears to be influenced by the host-strain genome.     

Bacteriophage ?29 DNA replication in vitro: Participation of the terminal protein and the gene 2 product in elongation

Summary From 29-infected Bacillus subtilis cells, we have isolated a protein fraction which promotes in vitro replication of 29 DNA. This fraction catalyses both initiation and elongation, indicating that it contains the product of gene 3 (tp: terminal protein) and the product of gene 2 (gp2: probably a DNA polymerase), since initiation requires the two products (Blanco et al. 1983; Matsumoto et al. 1983). The fractions isolated from cells infected with temperature-sensitive (ts) mutants of gene 2 and gene 3 were thermolabile in both the initiation and elongation assays. When the pre-initiated material from the ts fractions of each mutant was heat-inactivated and mixed no complementation, restoring the elongation activity, was found. These results indicate: (i) tp and gp2 participate not only in the initiation but also in the elongation of 29 DNA replication, (ii) they probably function in tight physical association with each other.Abbreviations gp2 product of gene 2 - tp terminal protein - DNAtp DNA with terminal protein covalently linked at both the 5 ends - ddCTP 2,3-dideoxycytidine 5-triphosphate - ddGTP 2,3-dideoxyguanosine 5 triphosphate     

Occurrence of pppApp-synthesizing activity in actinomycetes and isolation of purine nucleotide pyrophosphotransferase

The occurrence of adenosine 5-triphosphate-3-diphosphate-synthesizing activity was detected in five strains of actinomycetes; Streptomyces morookaensis, Streptomyces aspergilloides, Streptomyces hachijoensis, Actinomyces violascens and Streptoverticillium septatum, out of 825 strains of actinomycetes, bacteria, fungi and imperfecti. Purine nucleotide pyrophosphotransferase were extracellularly excreted associating with the cell growth, and were purified partially or to apparent homogeniety from the culture filtrate. The enzymes are a monomeric protein with a molecular weight of 18000–26000 and synthesize adenosine, guanosine and inosine 5-phosphate (mono, di or tri)-3-diphosphate such as pApp, ppApp, pppApp, pGpp, ppGpp, pppGpp and pppIpp by transferring a pyrophosphoryl group from the 5-position of ATP, dATP and pppApp to the 3-position of purine nucleotides in the presence of a divalent cation and in alkaline state.Abbreviations pppApp adenosine 5-triphosphate 3-diphosphate - ppApp adenosine 5-diphosphate 3-diphosphate - pApp adenosine 5-monophosphate 3-diphosphate - pppGpp guanosine 5-triphosphate 3-diphosphate     

Purification and characterization of a dimer form of the cAMP-dependent protein kinase from mouse liver cytosol

A protein kinase that phosphorylates histones and polysomal proteins was partially purified from mouse liver cytosol. The active enzyme has a molecular mass of 100 kDa and a phosphorylatable subunit of 54 kDa. Biochemical as well as immunological data suggest that the enzyme is a heterodimer composed of the catalytic subunit of cyclic AMP-dependent protein kinase and the R_II regulatory subunit. This RC form does not seem to dissociate upon activation with 3, 5 cyclic AMP and exhibits identical specificity as the classical cAMP-dependent protein kinase (2.7.1.37). The enzyme is affected by the 3, 5 cyclic phosphates of adenosine mainly, but also of guanosine, uridine and cytidine in a substrate-dependent manner. Cyclic nucleotides slightly stimulate phosphate incorporation into histones, while phosphorylation of polysomal proteins in intact polysomes is dramatically increased. The substrate- specific stimulatory effects of 3, 5 cyclic nucleotides are due to repression of the inhibition exerted upon the reaction, by negatively charged macromolecules such as RNA, DNA and to a lesser extent heparin.     

Degradation of RNA in Escherichia coli. A hypothesis

Summary A hypothesis to explain RNA degradation in Escherichia coli is proposed. In this hypothesis all classes of RNA are potentially degradable unless they are protected. The proposed mechanism for mRNA degradation requires a combination of endonuclease(s) and exonuclease(s) which degrades RNA in the 3 to 5 direction. Ribosomes attached to the newly synthesized 5 end of an mRNA molecule protect it from being attacked endonucleolytically; a delay in attachment of ribosomes to this end exposes it to endonucleolytic cleavage, followed by exonucleolytic digestion from the newly exposed 3 end to the 5 end. This mechanism is consistent with an overall 5 to 3 direction of degradation for mRNA. Exoribonucleases that degrade polyribonucleotides from the 5 end to 3 end are not required. The 3 end of the messenger is protected by its association with DNA. In order to enable the mRNA to remain anchored to the DNA while serving as an efficient template for protein synthesis, a special region near the 3 end of the mRNA is envisaged. This hypothetical region would not be translated.     

Formation of the imidazolides of dinucleotides under potentially prebiotic conditions

Summary Imidazolides of dinucleotides such as ImpApA can be formed from the corresponding dinucleotides in a two-stage process, which gives up to 15% yields under potentially prebiotic conditions. First a solution of the dinucleotide and sodium trimetaphosphate is dried out at constant temperature and humidity. This produces polyphosphates such as pnApA in excellent yield (80%). The products are dissolved in water, imidazole is added, and the solution is dried out again. This yields the 5-phosphorimidazolides.Abbreviations P₃! trimetaphosphate - A adenosine - U uridine - EDTA ethylenediaminetetraacetic acid - Ap adenosine 2(3)-phosphate - Ap! adenosine cyclic 2:3-phosphate - pA adenosine 5-phosphate - pA²p adenosine 2, 5-diphosphate - pA³p adenosine 3, 5-diphosphate - pAp! 5-phospho-adenosine cyclic 2:3-phosphate - ATP adenosine 5-triphosphate - ImpA adenosine 5-phosphorimidazolide - A²pA adenylyl-[25]-adenosine - A³pA adenylyl-[35]-adenosine - A²pU adenylyl-[25]-uridine - A³pU adenylyl-[35]-uridine - pA²pA 5-phosphoadenylyl-[25]-adenosine - pA³pA 5-phospho-adenylyl-[35]-adenosine - pA²pU 5-phospho-adenylyl-[25]-uridine - pA³pU 5-phospho-adenylyl-[35]-uridine - pApN (N= A, U) 5-phosphate of a dinucleoside phosphate - p_nApN (N = A, U; n = 2, 3, 4.) 5-polyphosphate of a dinucleoside phosphate - ImpA²pA imidazolide of pA²pA - ImpA³pA imidazolide of pA³pA - ImpA²pU imidazolide of pA²pU - ImpA³pU imidazolide of pA³pU - ImpApN imidazolide of pApN     

Poly(U)-directed peptide-bond formation from the 2′(3′)-glycyl esters of adenosine derivatives

Summary The self-condensation of 2(3)-O-glycyl esters of adenosine, adenosine-5-(O-methylphosphate) and P₁, P₂-diadenosine-5-pyrophosphate in 6.2 mM solutions at pH 8.0 and -5°C in the presence of 12.5 mM poly(U) yields approximately 3 times as much diketopiperazine as reactions without poly(U). As the concentration of 2(3)-O-(glycyl)-P₁, P₂-diadenosine-5-pyrophosphate is decreased from 6.2 mM to 1.5 mM the yield of diketopiperazine in the presence of poly(U) decreases slightly from 6.6% to 5.2%, whereas, in the absence of poly(U) the yield of diketopiperazine decreases substantially from 2.4% to 0.75%. The enhanced yield of diketopiperazine that is attributed to the template action of poly(U) is temperature dependent and is observed only at temperatures below 10°C (5°C to -5°C) for 6.2 mM 2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate) and below 23°C (15°C to -5°C) for 6.2 mM 2(3)-O-(glycyl)-P₁, P₂-diadenosine-5-pyrophosphate. The absence of a template effect at high temperatures is attributed to the melting of the organized helices. The hydrolysis half-lives at pH 8.0 and -5°C of 2(3)-O-(glycyl)-adenosine, 2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate), 2(3)-O-(glycyl)-P₁, P₂-diadenosine-5-pyrophosphate, and 5-O-(glycyl)-adenosine in the presence of poly(U) are substantially larger than their half-lives in the absence of poly(U). The condensation of 2(3)-O-(glycyl)-adenosine yields 5% of 5-O-(glycyl)-adenosine in the presence of poly(U) compared to 0.7% in the absence of poly(U).Abbreviations DKP diketopiperazine - (gly)₂ glycylglycine - (gly)₃ glycylglycylglycine - AppA-gly 2(3)-O-(glycyl)-P₁, P₂-diadenosine-5-pyrophosphate - MepA-gly 2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate) - Ado-2(3)-gly 2(3)-O-(glycyl)-adenosine - Ado-5-gly 5-O-(glycyl)-adenosine - Boc-gly N-tert-butyloxycarbonylglycine - AppA P₁, P₂-diadenosine-5-pyrophosphate - MepA adenosine-5-(O-methylphosphate) - AppA-Boc-gly 2(3)-O-(Boc-glycyl)-P₁, P₂-diadenosine-5-pyrophosphate - Ado-5-Boc-gly 5-O-(Boc-glycyl)-adenosine - Ado-2(3)-Boc-gly 2(3)-O-(Boc-glycyl)-adenosine     

Cyclic nucleotide phosphodiesterases of the renal cortex

Summary Cyclic nucleotide phosphodiesterase in the basal-lateral segment of plasma membranes from proximal tubule cells of the rabbit renal cortex was studied and compared to that in the brush border segment of the plasma membrane. Both adenosine 3,5-monophosphate and guanosine 3,5-monophosphate were hydrolyzed by the basal-lateral membrane, but activity varied differently with the two substrates in a complex concentration-dependent manner. Activity with adenosine 3,5-monophosphate was greater than, equal to, or less than with guanosine 3,5-monophosphate, at concentrations of 1000, 100, and 10 to 1 m, respectively. Basal-lateral membrane phosphodiesterase activities at 1 and 500 m substrate exhibited differential responses to pH, metals, heat, and a heat stable inhibitor. Stimulation by guanosine 3,5-monophosphate and inosine 3,5-monophosphate of adenosine 3,5-monophosphate hydrolysis was found in basal-lateral but not in brush border membranes. This stimulation was potentiated by ethyleneglycol-bis(-aminoethyl ether)N,N-tetraacetic acid and ethylenediaminetetraacetate, inhibited by Triton X-100, and totally blocked by Zn²⁺. The findings indicate that multiple forms of phosphodiesterase are present in the basal-lateral segment and these differ from the activities in the brush border region of the plasma membrane. The characteristics of (i) allosteric, guanosine 3,5-monophosphate-sensitivity of adensoine 3,5-monophosphate phosphodiesterase, and (ii) relatively high guanosine 3,5-monophosphate phosphodiesterase activity, in basal-lateral membranes, which are also enriched in adenylate and guanylate cyclase, suggest an important physiological role for these phosphodiesterases in the regulation of net production of cyclic nucleotides in the renal cortex.     

The structure of the incompatibility factors of Schizophyllum commune: Constitution of the three classes of B factors

Summary The B factors of Schizophyllum commune are of 3 classes: The high recombining class I has 7 alleles and 7 alleles; the low recombining classes are class II with 7 allels and probably 2 alleles and class III with probably 2 (or also 2) alleles and 7 allels. A fourth hypothetical class (-) was not found and either does not exist or is indistinguishable from class III by the tests employed. The and alleles differ from and by either (a) mutations affecting both mating specificity and recombination frequency, or (b) deletions involving most of the B region.The research was supported by a grant from the Atomic Energy Commission of the U.S. No. (30-1)-3875 and was performed at the Biological Laboratories, Harvard University, Cambridge, Mass., U.S.A.     

Cytochemical studies on the localization of 5′-nucleotidase in the acinar cells of the rat salivary glands

Summary The cytochemical localization of 5-nucleotidase (5-AMPase), and its validity, were investigated in parotid and submandibular acinar cells of a rat. Biochemical determinations showed that adequate treatment with glutaraldehyde could minimize the loss of enzymatic activity, and that 5-AMPase and non-specific alkaline phosphatase (-GPase) possessed different pH optima.The cytochemical distribution of the reaction products from the 5-AMPase activity was distinct from those of -GPase. 5-AMPase activity was localized on the surface membranes of acinar, ductal and myoepithelial cells of both salivary glands. -GPase activity was evenly distributed on the entire plasma membranes of myoepithelial cells and on the basal plasmalemma of acinar cells. The reaction products, which appeared on the luminal and lateral plasma membranes of the acinar cells, were presumed to reflect the presence of 5-AMPase, while those on the myoepithelial surface and basal plasma membranes of the acinar cells demonstrated both 5-AMPase and -GPase.The results indicate that 5-AMPase activity can be utilized as a reliable marker enzyme of plasma membranes in the salivary acinar cells.     

Analogues of NADP+ as inhibitors and coenzymes for NADP+ malic enzyme from maize leaves

Structural analogues of the NADP⁺ were studied as potential coenzymes and inhibitors for NADP⁺ dependent malic enzyme from Zea mays L. leaves. Results showed that 1, N⁶-etheno-nicotinamide adenine dinucleotide phosphate ( NADP⁺), 3-acetylpyridine-adenine dinucleotide phosphate (APADP⁺), nicotinamide-hypoxanthine dinucleotide phosphate (NHDP⁺) and -nicotinamide adenine dinucleotide 2: 3-cyclic monophosphate (23NADPc⁺) act as alternate coenzymes for the enzyme and that there is little variation in the values of the Michaelis constants and only a threefold variation in V_max for the five nucleotides. On the other hand, thionicotinamide-adenine dinucleotide phosphate (SNADP⁺), 3-aminopyridine-adenine dinucleotide phosphate (AADP⁺), adenosine 2-monophosphate (2AMP) and adenosine 2: 3-cyclic monophosphate (23AMPc) were competitive inhibitors with respect to NADP⁺, while -nicotinamide adenine dinucleotide 3-phosphate (3NADP⁺), NAD⁺, adenosine 3-monophosphate (3AMP), adenosine 2: 5-cyclic monophosphate (25AMPc), 5AMP, 5ADP, 5ATP and adenosine act as non-competitive inhibitors. These results, together with results of semiempirical self-consistent field-molecular orbitals calculations, suggest that the 2-phosphate group is crucial for the nucleotide binding to the enzyme, whereas the charge density on the C₄ atom of the pyridine ring is the major factor that governs the coenzyme activity.Abbreviations NADP⁺ 1, N⁶-etheno-nicotinamide adenine dinucleotide phosphate - NHDP⁺ nicotinamide-hypoxanthine dinucleotide phosphate - APADP⁺ 3-acetylpyridine-adenine dinucleotide phosphate - SNADP⁺ thionicotinamide-adenine dinucleotide phosphate - AADP⁺ 3-aminopyridine-adenine dinucleotide phosphate - 23NADPc⁺ -nicotinamide adenine dinucleotide 2: 3-cyclic monophosphate - 3NADP⁺ -nicotinamide adenine dinucleotide 3-phosphate - 2AMP adenosine 2-monophosphate - 3AMP adenosine 3-monophosphate - 23AMPc adenosine 2: 3 monophosphate cyclic - A adenosine - RuBP ribulose 1,5-bisphosphate - SCF-MO Self-Consistent Field-Molecular Orbitals (method)     

Effects of midazolam on the contraction and relaxation of segments of thoracic aorta stripped of endothelium and stimulated by adrenaline – experimental study in rabbits

To evaluate the effects of midazolam on the angiokinesis of segments of rabbits' thoracic aorta stripped of endothelium and stimulated by adrenaline.Two groups of aortic rings removed from albinic rabbits anesthetized with thiopental were used (Group I – 6 animals; Group II – 12 animals), stripped of endothelium, studied in an organ chamber, perfused by Krebs-Henseleit solution. The groups were stimulated by adrenaline, recording the maximum contraction and dT/dt at 12, 36, 60 and 120. When the plateau phase was reached, the vessel was washed with perfusion solution, recording relaxation at 2, 4 and 6. When the base values were reached, Group I underwent a new adrenergic stimulus; and Group II was stimulated with midazolam and then with adrenaline, and the same values were recorded. T test was applied as a statistical analysis when two variables were studied. When studying more than two variables the Anova test was used, supplemented by the Tuckey test.Group I did not show any significant difference between the two stimuli. Group II – the midazolam significantly reduced the maximum contraction induced by adrenaline (83.01 ± 4.11%) (p < 0.01). The dT/dt was reduced at 12 (57.06 ± 8.47%), and also at 36 (70.59 ± 5.26%). There was no significance at 60 and 120 (p < 0.01).The relaxation increased significantly at all measurements – at 2-adrenaline 39.31 ± 9.60%; adrenaline/midazolam: 44.06 ± 9.62% (p < 0.05). At 4-adrenaline: 53.08 ± 8.3%; adrenaline/midazolam: 61.68 ± 8.50% (p < 0.01). At 6-adrenaline: 76.26 ± 5.45%; adrenaline/midazolam: 84.20 ± 7.96% (p < 0.01).Midazolam significantly reduced the maximum contraction obtained by the adrenergic stimulus as well as the dT/dt in the initial phases of contraction. The relaxation speed also increased.     

Untersuchungen zum C′3-Polymorphismus (β 1c-Globulin)

Zusammenfassung Serumproben von 1322 Blutspendern aus Hessen, 40 Familien mit 89 Kindern, 20 Mutter-Kind-Kombinationen und 268 Sera einer Bantupopulation aus Portugiesisch Angola wurden mit einer modifizierten Technik der Hochspannungs-Dünnschichtelektrophorese auf Agarosegel hinsichtlich des C3-Polymorphismus untersucht. Die Genfrequenzen für Weiße (C3^S=0.779, C3^F=0.215) und Neger (C3^S=0.95, C3^F=0,048) stimmen gut mit den Werten anderer Autoren überein. Insgesamt ließen sich bei Weißen 9 Phänotypen sicher abgrenzen, bei Negern 3. Familienstudien bestätigten den für die Allele C3^S und C3^F angenommenen Vererbungsmodus (autosomal codominant) ausnahmslos. Die Frage der Lagerungsstabilität des C3 wurde abschließend untersucht.

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Investigations on C3-polymorphism ( _1c-Globulin)Gene frequencies and family studies in blood donors from Hessen and a Bantu population

Summary Serum samples of 1322 unrelated individuals from Hessen (Germany), 40 families with 89 children, 20 mother-child-combinations and 268 sera of a Bantu population from Angola were examined for C3 polymorphism using a modified technique of high voltage agarose gel electrophoresis. The gene frequencies for Caucasians (C3^S=0.779, C3^F=0.215) and negroes (C3^S=0.95, C^F=0.048) are in good accordance with those obtained by other authors. In total 9 different phenotypes were observed in Caucasians, 3 phenotypes in negroes. Family studies verify the supposed way of inheritance (autosomal codominant for C3^S and C3^F) without exception. Finally the problem of C3-inactivation by storage was investigated.