Evaluation of microbial testing methods for the mutagenicity of quinoline and its derivatives

Using the mutational enhancement method and the Ames test, the mutagenicity and potential carcinogenicity of quinoline and its derivatives were determined and compared. Quinoline, 8-hydroxyquinoline, 5-hydroxyquinoline, 8-hydroxyquinoline sulfate, 6-nitroquinoline, 8-nitroquinoline, and 3-methylquinoline were mutagenic in the Ames direct plating test on TA 98 and TA 100 with activating system (S-9) from the rat liver. These compounds were not mutagenic in the mutational enchancement test onEscherichia coli HCR+ strain. 5,7-Dichloro-8-hydroxyquinoline, isoquinoline, and 2-chloroquinoline were nonmutagenic without or with S-9 in both the Ames and mutational enhancement test system. The compounds chloroquine, primaquine diphosphate, quinine hydrobromide, quinine hydrochloride, quinine lactate, quinine urea hydrochloride, quinine ethylcarbonate, quinine dihydrochloride, beta quinine quinine valerate, and quinine glycerophosphate were nonmutagenic with and without S-9 in the Ames test but mutagenic (20–60 g/ml) in the mutational enhancement test method onEscherichia coli HCR+ strains. The observations reported here point out that the Ames test responds negatively to several quinoline derivatives that are positive in the mutational enchancement test method.     

Electron microscope study of the atretic oocytes of the rat

Zusammenfassung Das Muster in den Calcitindividuen des Eischalenkalkes der Vögel-seine Entstehung wird kurz erläutert — kann durch Spalten, Verwachsungsnähte, Anordnung der Globularinklusionen ohne weiteres hervortreten, läßt sich aber auch durch bestimmte Eingriffe, z. B. Ätzen, verdeutlichen. Quer- und Flachschliffe der Eischale von Diomedea exulans (Albatros) zeigen im Bereich der Säulenlage ein ausgeprägtes Globularmuster:In den Primen der Inneren Säulenlage erscheinen am Querschliff die Inklusionen in Parallelstreifen, die schräg gegen die Schalenoberfläche verlaufen, wobei die Neigung von einem zum anderen Prisma wechselt. Jede Reihe dieses Streifenmusters setzt sich aus rhombischen Elementen zusammen, derart, daß das eine Paar der Rhombenseiten die Längsränder des Streifens liefert, das andere aber, schräg über ihn verlaufend, seine Elemente trennt. Die Girlandenzone der Inneren Säulenlage wird durch den genannten Neigungswechsel des — hier vergröberten — Streifenmusters erzeugt.In der Äußeren Säulenlage häufen sich die Globularinklusionen in rechteckigen oder rhombischen Feldern an, die innerhalb des gleichen Prismas parallel stehen. Die Felder sind durch schmale helle inklusionsfreie Raine getrennt, in denen Verwachsungsnähte sich zeigen können. Dieses Block- oder Rhombenmuster ist auch am Flachschliff sichtbar.Der Übergang vom Streifenmuster der Inneren zum Rhomben- oder Blockmuster der Äußeren Säulenlage vollzieht sich über eine die Elemente durchschneidende Schichtlinie hinweg, ohne Störung der optischen Einheitlichkeit des Prismas. So kann das gleiche Musterelement unterhalb der Schichtlinie das Streifen-, oberhalb derselben das Blockmuster darbieten. Sowohl bei den Inneren wie bei den Äußeren Säulenprismen erfolgt die seitliche Verfugung der Nachbarn unter dem Einfluß des Musters, was bei den Inneren Säulen zackigen, bei den Äußeren mehr glatten Grenzverlauf erzeugt. Oft brechen Musterelemente an den Prismengrenzen ab. Manche Prismen der Inneren Säulenlage erscheinen am Flachschliff rhombisch umrissen. Auch am hügeligen Relief der Schalenoberfläche treten Rhombengrenzen hervor.

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Summary The pattern in the calcite individues of the avian egg shell — its development is shortly explained — can appear by clefts, outgrowing sutures, arrangement of the globular inclusions, but also can be rendered conspicuous by certain treatments, e.g. etching. Transverse and tangential ground sections through the egg shell of Diomedea exulans (albatros) show in the column layer a characteristic globular pattern.In the prisms of the inner column layer the inclusions are arranged on transverse sections in parallel stripes, running obliquely against the shell surface, whereby its inclination changes from one to the other prism. Each row of this stripe pattern is composed by rhombic elements, so that one pair of the rhomb sides form the longitudinal edges of the elements but the other, obliquely cutting the stripes, separate the elements. The garland zone of the inner column layer is the expression of the alternating inclination in the stripe pattern — here more coarse.In the outer column layer the globular inclusions are accumulated in rectangular or rhombic areas parallel within the same prism. The elements of this block or rhomb pattern are separated by narrow light inclusion-free hiels, in which outgrowing sutures can appear; the pattern is also visible in tangential ground sections.The transition of the stripe pattern to the rhomb or block pattern happens on a stratification line — without disturbance of the the uniform extinction of the prism between crossed polars. Thereby the same pattern element can show under the stratification line the stripe pattern and above it the block pattern. In the inner as in the outer column prisms the lateral indentation of the neighbours is determined by the pattern, producing in the inner columns a pronged, in the outer a more smooth boundary. Often pattern elements break off at the prism boundaries. Some prisms of the inner column layer show a rhombic contour in tangential ground sections. Also on the hilly relievo of the shell surface rhombic limitation is observable.

     

Decay of γ particles in germinating zoospores of Blastocladiella emersonii

Summary The breakdown and disappearance of particles was followed by electron microscopy on synchronously germinating populations of B. emersonii zoospores. The sequence of morphological changes, unaffected by the method used to induce germination, was divided into four stages. Initially, the particle's surrounding unit membrane becomes amorphous and buds off vesicles that fuse with the plasma membrane. Simultaneously, ca. 80 m vesicles are visible either partially embedded in, or lying free along, the inner surface of the electron dense matrix. These small vesicles seem to originate from a newly detected membrane system in the electron dense matrix. In the next stage, particles characteristically adhere to various organelles, especially the nuclear cap. In subsequent stages the particles continue to decay by releasing 80 m vesicles from their matrices and by budding off vesicles from their surrounding membranes. Often, multivesicular bodies are formed when the 80 m vesicles become enclosed by the particle's budding outer membrane. In the final stage, the surrounding membranes of the different particles fuse and produce large vacuoles containing many of the electron dense matrices which, though by now partially fragmented, continue to release 80 m vesicles. The relationship of the above events to the formation of the cell wall is discussed.     

Production of hemoglobin C in the Moufflon (Ovis musimon pallas, 1811) and the Barbary sheep (Ammotragus lervia pallas, 1777) during experimental anemia: Amino acid composition of tryptic peptides from the βB and βC chains

A hemoglobin ^C chain has been detected in anemic Moufflon and in anemic Barbary sheep. Results of limited structural studies suggest that these ^C chains are closely related to the ^C chains which are produced in the domestic sheep and goat during experimental anemia and rather different from the ^C chain of certain nonanemic Barbary sheep. The structural variability among the chains of some nonanemic Caprini species is greater than that observed for the ^C chains of the same animals.This research was supported in part by United States Public Health Service Research grant HE-05168.     

EDTA-assisted heavy-metal uptake by poplar and sunflower grown at a long-term sewage-sludge farm

Little information is available concerning the efficacy of chelates applied to biosolids (sewage-sludge)-treated soil for heavy-metal removal. The purpose of the experiment was to determine the availability to sunflower (Helianthus annuus L.) and hybrid poplar (Populus deltoides Marsh. × P. nigra L.) seedlings, of non-essential (Cd, Ni, Pb) and essential heavy metals (Cu, Fe, Mn, Zn) in field soil injected with biosolids since 1976 and treated with ethylenediamine-tetraacetic acid (EDTA) in 2001. Sunflower was grown at two densities, 20000 and 60000 plants/ha, and poplar at 10000 plants/ha. The tetrasodium salt of EDTA was applied at rates of 0, 0.5, 1, and 2 g EDTA salt per kg surface (25-cm depth) soil. The EDTA did not affect uptake by poplar of the three non-essential (Cd, Ni, Pb) and four essential (Cu, Fe, Mn, Zn) heavy metals. For sunflower, the 1.0 g/kg rate of chelate addition resulted in maximal removal of the three non-essential heavy metals (Cd, Ni, Pb). Uptake of the essential heavy metals by sunflower was little affected by the EDTA. At the 20000 plants/ha density, leaves of sunflower grown with 1.0 g EDTA Na₄2H₂O per kg soil accumulated more Cd, Ni, and Pb than leaves of sunflower grown without the EDTA salt. At this density, concentrations of Cd in leaves of sunflower without EDTA and with 1.0 g/kg EDTA salt were 2.2 and 6.5 g/g, respectively; for Ni, they were 6.7 and 19.2 g/g, respectively; and for Pb, they were 15.6 and 46.9 g/g, respectively. At the 60000 plants/ha density, stems of sunflower grown with 1.0 g EDTA Na₄2H₂O per kg soil accumulated more Cd, Ni, and Pb than stems of sunflower grown without the EDTA salt. At this density, concentrations of Cd in stems of sunflower without EDTA and with 1.0 g/kg EDTA salt were 0.6 and 4.6 g/g, respectively; for Ni, they were 1.7 and 17.6 g/g, respectively; and for Pb, they were 5.2 and 42.8 g/g, respectively. Removal of the non-essential heavy metals by sunflower was greater at the higher plant density (60000 plants/ha) compared to the lower one (20000 plants/ha).     

Über die Eignung von Naphthyl-α-l-fucosiden zur Untersuchung der α-l-Fucosidasen

Zusammenfassung Verglichen mit 1- und 2-Naphthyl--d-glucosid,--d-galactosid,--d-glucuronid,--d-N-acetylglucosaminid,--d-glucosid,--d-galactosid und--d-mannosid werden 1- und 2-Naphthyl--l-fucosid schneller oder im gleichen Ausmaß von Homogenaten verschiedener Rattenorgane hydrolysiert. Trotzdem fällt der histochemische Nachweis der -l-Fucosidasen methodenunabhängig im Gegensatz zu dem der anderen Glykosidasen überwiegend negativ aus. Ursache dafür ist die massive Hemmung der -l-Fucosidase durch Aldehydfixation und Diazoniumsalze; die Inhibitionsrate liegt bei 90% bzw. zwischen 85 und 98%; die - und -d-Glucosidase, - und -d-Galactosidase, -d-Mannosidase, -d-Glucuronidase sowie -d-N-Acetylglucosaminidase werden durch Aldehydfixation oder Kuppler höchstens zu 70% gehemmt. Daher können 1- und 2-Naphthyl--l-fucosid für die histochemische Darstellung der -l-Fucosidase nicht einschränkungslos empfohlen werden. Kleine Mengen Dimethylformamid hemmen die meisten Glykosidasen nicht.Für biochemische Messungen der -l-Fucosidase eignet sich speziell 1-Naphthyl--l-fucosid und läßt sich an Stelle von p-Nitrophenyl--l-fucosid werwenden. Bei der fluorometrischen Untersuchung der -l-Fucosidase in Rattenorganen mit dem 2-Naphthylderivat ergeben sich bemerkenswerte Aktivitätsunterschiede.

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Suitability of naphthyl--l-fucosides for the investigation of -l-fucosidases

Summary In comparison with 1- and 2-naphthyl -d-glucoside, -d-galactoside, -d-glucuronide, -d-N-acetylglucosaminide, -d-glucoside, -d-galactoside and -d-mannoside 1- and 2-naphthyl -l-fucoside are hydrolyzed more quickly or to the same extent by homogenates prepared from freezedried cryostate sections of various rat organs. Nevertheless, when the fucosides are employed for the histochemical demonstration of -l-fucosidase mostly negative data were obtained independent on the method used, whereas all other naphthyl glycosides deliver positive results. The reasons for these discrepancies are the marked inhibition of -l-fucosidase by aldehyde fixation and diazonium salts. Then, -l-fucosidase activity is suppressed to 90% and between 85 and 98% respectively; the inhibition of - and -d-glucosidase, - and -d-galactosidase, -d-mannosidase, -d-glucuronidase and -d-N-acetylglucosaminidase by the fixative or coupling reagent does not exceed 70%. Therefore 1- and 2-naphthyl -l-fucoside cannot be recommended in general for histochemical purposes. Small amounts of dimethylformamide do not influence the activity of most of the glycosidases investigated.For biochemical measurements, however, especially 1-naphthyl -l-fucoside represents a suitable alternative in a fluorometric procedure instead of p-nitrophenyl -l-fucoside used for the photometric evaluation of -l-fucosidase. With the fluorometric method the enzyme was measured in rat organs, which posses remarkably different activities of -l-fucosidase.

     

Variant forms ofα-2-l-fucosyltransferase in human submaxillary glands from blood group ABH “secretor” and “non-secretor” individuals

The properties of the -2-l-fucosyltransferases in submaxillary gland preparations from blood group ABH secrefors and non-secretors were compared. The level of activity in the non-secretor gland homogenates amounted to about 5% only of that found in the secretor gland preparations. The enzymes from the two sources differed in solubility properties, charge and affinities for donor and acceptor substrates. The enzyme from secretor glands showed a preference for acceptors with Type 1 [d-galactosyl(1–3)-N-acetyl-d-glucosamine] structures whereas the enzyme from non-secretor glands had a preference for Type 2 [d-galactosyl(1–4)-N-acetyl-d-glucosamine] structures.These results demonstrate that expression of the secretor gene (Se) is associated with a molecular form of the -2-l-fucosyltransferase that is different from the species present in the same tissue when theSe gene is not expressed.     

Gibberellins play a role in the interaction between imidazole fungicides and cytokinins in Araceae

Imidazole fungicides such as imazalil, prochloraz, and triflurnizole and the triazole growth retardant paclobutrazol promote the shoot-inducing effect of exogenous cytokinins in Araceae, such as Spathiphyllum floribundum Schott and Anthurium andreanum Schott. The mechanism of their action could partially be based on the inhibition of gibberellic acid (GA) biosynthesis, because administration of GA₃ inhibits the phenomenon completely in S. floribundum. Not only is the suppression of GA biosynthesis involved, but also the metabolism of endogenous cytokinins is significantly altered. Although the balance between isopentenyladenine, zeatin, dihydrozeatin, and their derivatives was shifted to distinguished directions by administration of BA and/or imazalil and/or GA₃, no correlation between these changes in metabolic pathways and the number of shoots could be found. The metabolism of BA was not significantly altered by adding imazalil to the micropropagation medium of S. floribundum.Abbreviations 2,4-D 2,4-dichlorophenoxyacetic acid - [9R-5P]DHZ 9--d-ribofuranosyl-dihydrozeatin-monophosphate - [9R-5P]iP 6-isopentenyl-9--d-ribofuranosyladenine-monophosphate - [9R-5P]Z 9--d-ribofuranosyl-zeatin-monophosphate - [9G]BA 6-benzyl-9--d-glucopyranosyladenine - [9G]DHZ 9--d-glucopyranosyl-dihydrozeatin - [9G]iP 6-isopentenyl-9--d-glucopyranosyladenine - [9G]Z 9--d-glucopyranosyl-zeatin - [9R]BA 6-benzyl-9--d-ribofuranosyladenine - [9R]DHZ 9--d-ribofuranosyl-dihydrozeatin - [9R]iP 6-isopentenyl-9--d-ribofuranosyladenine - [9R]Z 9--d-ribofuranosyl-zeatin - BA 6-benzyladenine - DHZ dihydrozeatin - ES⁺ LC-MS/MS HPLC coupled Electrospray Tandem Mass Spectrometry - f.m. fresh mass - mT 6-(3-hydroxybenzyl)adenine - IMA imazalil - iP isopentenyladenine - NAA 1-naphthalene acetic acid - NFT Nutrient Film Technique - (OG)[9R]DHZ O--glucopyranosyl-9--d-ribofuranosyl-dihydrozeatin - (OG)[9R]Z O--d-glucopyranosyl-9--d-ribofuranosyl-zeatin - (OG)DHZ O--d-glucopyranosyl-dihydrozeatin - (OG)Z O--d-glucopyranosyl-zeatin - PAR Photosynthetic Active Radiation - PBZ paclobutrazol - PRO prochloraz - TDZ thidiazuron - TRI triflurnizole - Z zeatin     

Life cycle of Porphyra vietnamensis Tanaka & Pham-Hoang Ho from Thailand

Porphyra vietnamensis Tanaka & Pham-Hoang Ho is a tropical species of high potential for farming. Studies of the life cycle have been conducted for many years but have not been successful until recently. Mature thalli were collected from Songkhla, in the southern part of Thailand, and were used to obtain Conchocelis in the laboratory in Bangkok. Conchocelis in shells as well as free-floating filaments could be observed after one week of incubation at 25 °C, 25 salinity and 350–500 lux light intensity, and covered the culture shell surface within 2 months. Conchosporangia were formed after being incubated for 10 days at 30 °C, 20 salinity under light intensities of 350–500 lux with a photoperiod of 12 hours a day. Induction of conchospore release was achieved by lowering the temperature to 25 °C and the salinity to 10–15 and increasing the light intensity to 800–1000 lux. Liberated conchospores germinated into young thalli which became mature after 70 days.     

Bewegungsstudien an Anatinen

Zusammenfassung Vorliegende Arbeit ist eine Weiterführung derLorenz'schen Bewegungsstudien an Anatinen aus dem Jahre 1941, fortgesetzt an Mischlingen zwischen den dort beschriebenen Arten. Die sich dabei ergebenden Befunde machten eine erneute Untersuchung der Elternarten notwendig. Außerdem wurden einige Arten beobachtet, deren Verhalten noch nicht untersucht worden war. Fragestellung und Begründung werden in der Einleitung gegeben.Im zweiten Abschnitt werden einige der vonLorenz gemachten Beobachtungen berichtigt. So zeigten einige der Kreuzungen mitbahamensis, daß die vonLorenz bei eben dieser Art als Kurzhoch-werden bezeichnete Bewegungsweise dem Ab-auf anderer Schwimmenten homolog ist. Ebenso ist die eine der beiden vonLorenz als Kurzhoch-werden bezeichneten Verhaltensweisen des Krickerpels als Ab-auf zu deuten. Der Gruß desflavirostre-Erpels wurde auch bei weiblichen Tieren gesehen. BeiAnas acuta wurde ein Kinnheben festgestellt, das sich in der Form stark vom Kinnheben beiplatyrhynchos unterscheidet. Als neue Verhaltensweisen wurden u. a. das Haltungannehmen und das Tendieren beimflavirostre-Erpel beschrieben.Im dritten Abschnitt werden einige Verhaltensweisen und ihre Funktion diskutiert und der Versuch gemacht, eine Motivationsanalyse zu geben.(Zeichnungen vonHermann Kacher)     

Production of β-fructofuranosidase byAspergillus japonicus

A newly isolated strain, MU-2, which produces very high -fructofuranosidase activity, was identified asAspergillus japonicus. For enzyme production by the strain, sucrose at 20% (w/v) was the best carbon source and yeast extract at 1.5 to 3% (w/v) the best nitrogen source. Total enzymatic activity and cell growth were at maximum after 48 h, at 1.57×10⁴ U/flask and 0.81 g dry cells/flask, respectively. The optimum pH value of the enzymatic reaction was between 5.0 and 5.5 and the optimum temperature 60 to 65°C. The enzyme produced 1-kestose (O--d-fructofuranosyl-(21)--d-fructofuranosyl -d-glucopyranoside) and nystose (O--d-fructofuranosyl-(21)--d-fructofuranosyl-(21)--d-fructofuranosyl -d-glucopyranoside) from sucrose by fructosyl-transferring activity. The strain was found to be very useful for industrial production of -fructofuranosidase.     

Isolation and characterization of β-glucosidases from Aspergillus nidulans mutant USDB 1183

Two extracellular -glucosidases (cellobiase, EC 3.2.1.21), I and II, from Aspergillus nidulans USDB 1183 were purified to homogeneity with molecular weights of 240,000 and 78,000, respectively. Both hydrolysed laminaribiose, -gentiobiose, cellobiose, p-nitrophenyl--L-glucoside, phenyl--L-glucoside, o-nitrophenyl--L-glucoside, salicin and methyl--L-glucoside but not -linked disaccharides. Both were competitively inhibited by glucose and non-competitively (mixed) inhibited by glucono-1,5-lactone. -Glucosidase I was more susceptible to inhibition by Ag⁺ and less inhibited by Fe²⁺ and Fe³⁺ than -glucosidase II.     

Enzymic synthesis of lacto-N-triose II and its positional analogues

N-acetylhexosaminidase fromNocardia orientalis catalysed the synthesis of lacto-N-triose II glycoside (-d-GlcNAc-(1-3)--d-Gal-(1-4)--d-Glc-OMe,3) with its isomers -d-GlcNAc-(1-6)--d-Gal-(1-4)--d-Glc-OMe (4) and -d-Gal-(1-4)-[-d-GlcNAc-(1-6)]--d-Glc-OMe (5) throughN-acetylglucosaminyl transfer fromN,N-diacetylchitobiose (GlcNAc₂) to methyl -lactoside. The enzyme formed the mixture of trisac-charides3, 4 and5 in 17% overall yield based on GlcNAc₂, in a ratio of 20:21:59. Withp-nitrophenyl -lactoside as an acceptor, the enzyme also producedp-nitrophenyl -lacto-N-trioside II (-d-GlcNAc-(1-3)--d-Gal-(1-4)--d-Glc-OC₆H₄NO₂-p,6) with its isomers -d-GlcNAc-(1-6)--d-Gal-(1-4)--d-Glc-OC₆H₄NO₂-p (7) and -d-Gal-(1-4)-[-d-GlcNAc-(1-6)]--d-Glc-OC₆H₄NO₂-p (8). In this case, when an inclusion complex ofp-nitrophenyl lactoside acceptor with -cyclodextrin was used, the regioselectivity of glycosidase-catalysed formation of trisaccharide glycoside was substantially changed. It resulted not only in a significant increase of the overall yield of transfer products, but also in the proportion of the desired compound6.Abbreviations GlcNAc₂ 2-acetamido-2-deoxy--d-glucopyranosyl-(1-4)-2-acetamido-2-deoxy-d-glucose - NAHase N-acetylhexosaminidase - -CD -cyclodextrin     

A comparison and evaluation of some phytosociological techniques

Summary In three areas of vegetation (dune, mountain heath and salt marsh) the following phytosociological techniques have been tested and compared, using the same data: the Braun-Blanquet method; association and inverse analysis ofWilliams &Lambert; cluster analysis (agglomerative classification) based on different coefficients of similarity; and ordination (principal components analysis performed on matrices of different coefficients).The Braun-Blanquet method is considered to combine several advantages of the other methods and to be most economical in terms of efficiency (ratio of time input to information emerging).

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Zusammenfassung Auf drei verschiedenen Vegetationsflächen (Bergheide, Küstendünen und Salzwiesen) sind die folgenden pflanzensoziologischen Methoden geprüft und verglichen worden: die Methode von Braun-Blanquet; association analysis vonWilliams &Lambert (1959, 1961); Ordination (principal components analysis); und cluster analysis (Sokal &Sneath, 1963). Die letzteren beiden wurden mit verschiedenen Ähnlichkeitskoeffizienten geprüft.Auf Grund solchen Erfahrungen, zeigte sich die Braun-Blanquetische Methode leistungsfähiger als die anderen Methoden (d.h. optimale Einsicht in der Vegetation pro Arbeitsstunde). Sie vereinigte viele Vorteile der anderen Methoden.

     

Die bursa- und schwanzstrukturen und ihre aberrationen bei den strongylina (Nematoda) morphologische studien zum problem der pluri-und paripotenzerscheinungen

Zusammenfassung In der Einleitung ist das Ziel der Arbeit in den wesentlichsten Punkten herausgestellt.Die Bursastrukturen (Bursavelum und Rippen bzw. Papillen) der parasitischen Strongylina lassen sich von den entsprechenden Bildungen der freilebenden Rhabditina, vor allem der Gattung Rhabditis, ableiten und in ihren Einzelgliedern homologisieren.Die im Laufe der Phylogenie bei den Strongylina auftretenden strukturellen Transformationen lassen sich auf einige wenige, relativ einfache morphogenetische Grundvorgänge zurückführen, die da sind: Wachstumsallometrien, Materialkompensationen, Organverschmelzungen und Spaltungen (Fissationen), Rudimentationen und ähnliche Vorgänge.Innerhalb der Strongylina Bursa ist ein Gefälle der Wachstumsgradienten feststellbar, das sich vom Zentrum der Bursa sowohl nach distal als auch proximalwärts abschwdcht. Zunehmende Förderung der zentral gelegenen Organe (Rippen) führt zu entsprechender Reduktion der peripheren Bursastrukturen, was vor allem im terminalen Schwanzabschnitt auffällt und zur Ausbildung des oft nur noch als Rudiment vorhandenen Dorsalrippenkomplexes führt. Letzterer entspricht in seiner Gesamtheit der Schwanzspitze der peloderen Rhabditiden mit den Papillen 9 und 10.Die bei Rhabditis moist getrennten Papillen 7 und 8 sind bei allen Strongylina zu einer Rippe (Externodorsal-Rippe) verschmolzen, die jedoch in manchen Aberrationen durch Abspaltung eines akzessorischen Astes ihre wahre Natur (als Verschmelzungsprodukt) zu erkennen gibt (Atavismus).Da dieselben Transformationsvorgänge innerhalb der Strongylina mehrfach unabhängig voneinander wirksam geworden sind, treten bestimmte Strukturformen als Parallelbildungen in verschiedenen phylogenetischen Union auf (polytope Entstehung).Zahlreich untersuchte Bildungsabweichungen (Aberrationen), deren Bedeutung für die Morphologie kurz umrissen wird, erschöpfen sich in den gleichen strukturellen Transformationstypen, die auch bei der Evolution der verschiedenen Union der Strongylina nachweisbar sind. Die Aberrationen führen daher häufig zu Atavismen oder zu Parallelvariationen (homologe Variationen").Die Zahl der Umwandlungsmbglichkeiten (Potenzen) der Bursastrukturen innerhalb der Strongylina ist beschränkt (Paripotenz im Sinne Haeckers). Bestimmte Arten (und Entwicklungshnien) haben jeweils nur bestimmte Potenzen realisiert. Andere können jedoch latent (virtuell) im Kryptotypus vorhanden sein, ohne normalerweise in Erscheinung. zu treten. In bestimmten Aberrationen können sie jedoch plötzlich realisiert werden, so ihr latentes Vorhandensein demonstrierend (Pluripotenz).Wie lange bestimmte Potenzen in einer Gruppe erhalten bleiben konnen, verdeutlichen auch die Schwanzhocker weiblicher Nematoden, als zum Bauplan der Nematoden gehbrende Bildungen. Die Potenz zur Ausbildung dieser Strukturen kommt offensichtlich sehr vielen Nematoden-Arten zu, wird jedoch nur in relativ wenigen Fällen, aber innerhalb der verschiedenen Gruppen bald hier, bald dort (disjunkte Verbreitung), realisiert. Es handelt sich bei den Schwanzhöckern um rudimentäre Organe, die bei keiner Nematoden-Art mehr voll ausgebildet erhalten sind. Ihre Rudimentation beruht zum Teil auf Materialentzug, als Folge von Unkonstruktionen der Schwanzregion, wobei die Adultstadien zuerst betroffen werden (Aphanisie nach Sewertzoff).Bei den in Chiropteren parasitierenden Strongylacanthinae haben sich Schwanzhöcker noch bei allen Arten erhalten, was ein offensichtlich archaisches Merkmal darstellt. Bei anderen Nematoden, denen sie nur im Larvalstadium zukommen, treten sie wohl durch Fötalisation in seltenen Fällen auch bei den adulten Stadien wieder auf.Alle speziellen Bursaformen der Strongylina lassen sich durch relativ wenige und einfache Transformationsvorgänge aus einem durch Abstraktion gewonnenen diagrammatischen Typus ableiten (Prinzip der variablen Proportionen" nach Troll).Die typisierten Umwandlungsvorgänge decken sich weitgehend mit den von Remane allgemein gefaßten strukturellen Typen der Realmutationen. Da sie bei den beobachteten Aberrationen, deren Entstehung auf dem Wege über Realmutationen sehr wahrscheinlich ist, in homologer Weise auftreten, kann das innerhalb der Strongylina zu beobachtende Evolutionsphänomen auf Realmutationen zurückgeführt warden.Obwohl sich die untersuchten strukturellen Transformationen in dem systematisch relativ wait gefaßten Rahmen einer Unterordnung abspielen (transspezifische Evolution nach Rensch), handelt es sich bei der von uns bevorzugten Terminologie (nach Woltereck und Remane), unter Berücksichtigung des Charakters der Umwandlungen, doch nur um Vorgänge, die in den Bereich der Mikroevolution fallen.     

Incorporation of [32P]- and [14C]-ATP intoEscherichia coli isocitrate lyase

InEscherichia coli, isocitrate lyase has been shown to be phosphorylated in vitro by [-³²P]-ATP on histidine residues. This phosphorylation is believed to be necessary for activity of this enzyme. Previous work has shown that treatment of isocitrate lyase with acid phosphatase leads to a decrease in activity as well as a loss of incorporated [³²P]-phosphate in a time-dependent manner. In addition to phosphorylation by [-³²P]ATP, isocitrate lyase has been found to incorporate radioactive label from [-³²P]ATP and from [¹⁴C]ATP. This finding may indicate that more than one type of covalent modification occurs on this enzyme. Isocitrate lyase activity, inE. coli, may be regulated by posttranslational modification in several ways.     

Purification and characterization of α(2-6)-sialyltransferase from human liver

A Gal1-4GlcNAc (2-6)-sialyltransferase from human liver was purified 34 340-fold with 18% yield by dye chromatography on Cibacron Blue F3GA and cation exchange FPLC. The enzyme preparation was free of other sialyltransferases. It did not contain CMP-NeuAc hydrolase, protease, or sialidase activity, and was stable at –20°C for at least eight months. The donor substrate specificity was examined with CMP-NeuAc analogues modified at C-5 or C-9 of theN-acetylneuraminic acid moiety. Affinity of the human enzyme for parent CMP-NeuAc and each CMP-NeuAc analogue was substantially higher than the corresponding Gal1-4GlcNAc (2-6)-sialyltransferase from rat liver.Abbreviations FPLC fast protein liquid chromatography - NeuAc 5-N-acetyl-d-neuraminic acid - 9-amino-NeuAc 5-acetamido-9-amino-3,5,9-trideoxy-d-glycero-2-nonulosonic acid - 9-acetamido-NeuAc 5,9-diacetamido-3,5,9-trideoxy-d-glycero--d-2-nonulosonic acid - 9-benzamido-NeuAc 5-acetamido-9-benzamido-3,5,9-trideoxy-d-glycero--d-galacto-2-nonulosonic acid - 9-fluoresceinyl-NeuAc 9-fluoresceinylthioureido-NeuAc - 5-formyl-Neu 5-formyl--d-neuraminic acid - 5-aminoacetyl-Neu 5-aminoacetyl--d-neuraminic acid - CMP-NeuAc cytidine-5-monophospho-N-acetylneuraminic acid - G_M1 Gal1-3GalNAc1-4(NeuAc2-3)Gal1-4Glc-ceramide - ST sialyltransferase - DTE 1,4-dithioerythritol Enzyme: Gal1-4GlcNAc (2-6)-sialyltransferase, EC 2.4.99.1.     

A fluorometric assay of ceramide glycanase with 4-methylumbelliferyl β-d-lactoside derivatives

4-Methylumbelliferyl 6-O-benzyl--d-lactoside (6Bn-MU-Lac) and some related compounds were synthesizedvia different selective reactions including phase-transfer glycosylation. Their suitability as substrates for a fluorometric assay of ceramide glycanase (CGase) was evaluated. Among others, the 6Bn-MU-Lac, which is resistant to exogalactosidase, was found to be a suitable substrate for routine assay of the CGase activity. For American leech CGase, theK _m value is 0.232 mM at pH 5. Abbreviations: CGase, ceramide glycanase; Gal, galactose; Glc, Glucose; Lac, lactose; MU, 4-methylumbelliferone; MU-Lac, 4-methylumbelliferyl -d-lactoside; bBn-Lac, 6-O-benzyl-lactose; 6Bn-MU-Lac, 4-methylumbelliferyl 6-Obenzyl--d-lactoside; 46Bd-MU-Lac, 4-methylumbelliferyl 4,6-O-benzylidene--d-lactoside; MU-Cel, 4-methylumbellifery -d-cellobioside; 46Bd-MU-Cel, 4-methylumbelliferyl 4,6-O-benzylidene--d-cellobioside; TLC, thin layer chromatography;¹H-NMR, proton nuclear magnetic resonance; GSL, glycosphingolipids; CSA, 10-camphorsulfonic acid. See Scheme 1 for chemical structures.     

Methylobacterium rhodesianum MB 126 possesses two acetoacetyl-CoA reductases

Two constitutive acetoacetyl-CoA (AcAc-CoA) reductases were purified from Methylobacterium rhodesianum MB 126, an NADPH-linked d(-)--hydroxybutyryl-CoA forming reductase (enzyme A) and an NADH-and NADPH-linked l(+)--hydroxybutyryl-CoA forming reductase (enzyme B). Enzyme A and B give apparent K _m values of 15 M and 30 M for AcAc-CoA, 18 M for NADPH and 30 M for NADH, respectively. They are inhibited by AcAc-CoA at concentrations higher than 25 M and 50 M, respectively. The contribution of the two reductases to poly--hydroxybutyrate synthesis is discussed.     

Rabbit heavy chain haplotypes — Allotypic determinants expressed byVH-CH recombinants

This report summarizes our current understanding of the heavy chain haplotypes found in our laboratories' rabbits. Independently derived data from several laboratories have been synthesized into a consistent picture of the linked inheritance of allotypic markers found on the different heavy chain classes and subclasses of rabbit immunoglobulins in pedigreed rabbits, including the families of three apparentVH-CH recombinants. In one recombinant, the entire group ofCH markers (C, C, and C) recombined with the set ofVH. Although in the other two recombinants all CH markers may also have recombined as a group, in one of these only IgG and IgACH genes were informative; in the other recombinant, only the IgG allotypes were informative. Some allotypic determinants found on IgM molecules (conformational) appear only when a specific variable region allotype (VHa) is combined with a specific constant region allotype (C). New combinations ofVHa and C allotypes were generated in two of the genetic recombinants and led to new conformational determinants. The gains and losses observed lend support to the hypothesis that the determinants result from conformations generated by the combination of allotype-specificVH and C protein sequences. Conceivably, DNA events that joinVH to diversity (D)- and joining (J)-coding sequences or mRNA processing events that splice J to C could be involved in generating the sequences that form allotype-specific determinants.