Volatile and gaseous metabolites released by germinating seeds of lentil and maize cultivars with different susceptibilities to fusariosis and smut

The effect of volatile and gaseous metabolites released by germinating seeds of lentil cultivars more and less susceptible to fusariosis on the germination of spores ofMucor racemosus, Trichoderma viride, Verticillium dahliae andBotrytis cinerea was found to depend rather on the fungal genus than on the lentil cultivar. However, spores ofFusarium oxysporum reacted more sensitively during germination to the presence of exudates of both cultivars, when the more susceptible lentil displayed a stimulation, the less susceptible one an inhibition of spore germination. The greatest difference in the effect of exudates was observed in the more and less susceptible maize cultivars with respect to the germination of chlamydospores ofUstilago maydis, especially during the first hours of seed germination. Analysis of the exudates of germinating seeds showed the release of a greater amount of ethanol and methanol with acetaldehyde by the more susceptible cultivars of lentil and particularly maize.     

A 13c-n.m.r. study of 1,6:2,3- and 1,6:3,4-dianhydro-β-D-hexo-pyranoses and their O-acetyl and deoxy derivatives

¹³C-N.m.r. spectra of all possible 1,6:2,3- and 1,6:3,4-dianhydro-β-D-hexo-pyranoses and their O-acetyl and deoxy derivatives are presented. Relations between chemical shifts of certain carbon atoms and the structure of the dianhydrides are outlined, and their application in structural analysis is discussed. Inversion of configuration of the oxirane ring from the endo to the exo position is associated with typical upfield-shifts for oxirane-ring carbon atoms C-2 or C-4, respectively. Possible inter-relationships between ¹³C-chemical shifts and steric and polar interactions in the dianhydro derivatives are discussed.     

Lipids of higher fungi. III. The fatty acids and 2-hydroxy fatty acids in some species of Basidiomycetes

Total fatty acids derived from 12 species of mushrooms were separated into fatty acid and 2-hydroxy fatty acid fractions (FA and HFA), and analyzed quantitatively. The HFA content varied from 0 to 22% of total fatty acids. The major fatty acids were 16:0, 18:0, 18:1, 18:2, and the major 2-hydroxy fatty acids were h16:0, h18:0, h22:0, h24:0. The predominant HFA in the mushrooms investigated had chain-lengths greater than 20 C-atoms, and were derived from sphingolipids — ceramides and cerebrosides.     

Importance of the flux of phosphate across the inner membrane of kidney mitochondria for the activation of glutaminase and the transport of glutamine

The effect of mersalyl, an inhibitor of phosphate transport across the inner mitochondrial membrane, was investigated on the uncoupled respiration of pig kidney mitochondria in the presence of glutamine as substrate and on the activity of the phosphate-dependent glutaminase in the intact organelles. In addition, the submitochondrial location of the enzyme was reinvestigated.

1. (1) It was found that mersalyl completely inhibits uncoupled respiration of the mitochondria in the presence of glutamine as substrate, whereas respiration with glutamate was not affected. The same amount of mersalyl which inhibits coupled oxidation of glutamine also inhibits coupled oxidation of glutamate and some other substrates.

2. (2) Mersalyl strongly inhibited the activation of glutaminase in intact mitochondria only in the presence of inhibitors of electron transport or of an uncoupler. The addition of a detergent prevented or fully released the inhibition. The effect of mersalyl was observed even when the mitochondria were pre-incubated with phosphate or incubated in the phosphate-free medium. If mersalyl and carbonyl cyanide m-chlorophenylhydrazone (CCCP) were added 3 min after pre-incubation with phosphate the same intramitochondrial concentration of the anion as in control experiments was found, whereas the activity of glutaminase was severely inhibited. These findings suggest that the activation of the enzyme by phosphate in intact nonenergized mitochondria occurs only if the activator moves across the inner mitochondrial membrane.

3. (3) Mersalyl (plus CCCP) markedly decreased [¹⁴C]glutamine- and [³²P]-phosphate-permeable mitochondrial spaces. A close correlation between the decrease of phosphate and glutamine permeable spaces and the inhibition of glutaminase activity was found.

4. (4) If the activation energy of the enzyme was determined with frozen mitochondrial preparations, a discontinuity or break in the Arrhenius plot was observed, whereas the presence of a detergent completely abolished the break. Digitonin or ultrasonic treatment of the mitochondria followed by separation of the membrane and the soluble fraction revealed that glutaminase is a membrane-bound enzyme.

On the basis of these findings it is concluded that there is an association between the transport of phosphate on one side and the transport of glutamine and glutaminase activity on the other. It is possible that the movement of phosphate across the membrane activates the enzyme which facilitates diffusion of glutamine down a concentration gradient. However, the existence of a specific glutamine-phosphate carrier is not ruled out.     

Cell cooperation in abolition of tolerance of xenogeneic tumor.

Thymectomized, lethally irradiated mice reconstituted with syngeneic bone marrow cells are tolerant to xenogeneic Yoshida ascites sarcoma (YAS). The tolerance was abolished by an injection of syngeneic normal spleen, thymus, or lymph node cells given simultaneously with YAS. Allogeneic and semiallogeneic spleen cells were ineffective. The YAS-rejecting mice produced specific anti-tumor antibodies. The serum of these mice transferred to tolerant T-cell-deficient mice protected the latter from inoculated YAS cells. These serum-protected mice were not able to resist the reinoculum of the tumor cells as the mice restored with lymphoid cells did. The latter mice rejected the YAS at the time when donor cells were practically absent in their lymphoid tissue. The low effective ratio of injected syngeneic lymphoid to tumor cells, efficiency of injected thymus cells, and other data led to the conclusion that transferred lymphoid cells did not act directly on tumor cells but through cooperation with host lymphoid cells. The cooperation of donor T- and host B-lymphocytes enabled the activation of the latter, and YAS cells were rejected.     

Synthesis and chemical behaviour of D-glucosyl esters of glutamic acid having the side-chain carboxyl group involved in the glycosidic linkage.

Simultaneous and stepwise deprotection of the fully benzylated D-glucosyl esters of 1-benzyl N-benzyloxycarbonyl- and N-tert-butyloxycarbonyl-L-glutamic acid (1 and 5, respectively) have been examined. Catalytic hydrogenation of 1 led to intramolecular aminolysis to give pyroglutamic acid and D-glucose, but similar treatment in the presence of trifluoroacetic acid afforded both anomers of 1-O-(L-gamma-glutamyl)-D-glucopyranose, which were characterized as trifluoroacetates (2alpha and 2beta) and converted into 2,3,4,6-tetra-O-acetyl-1-O-[1-methyl N-(acetyl)-L-glutam-5-oyl]-D-glucopyranose (4) which was also prepared by a definitive method. Hydrogenolysis of 5 gave both anomers of 1-O-[N-(tert-butyloxycarbonyl)-L-gamma-glutamyl]-D-glucopyranose (6), which, upon treatment with trifluoroacetic acid at - 10 degrees, afforded 2alpha and 2beta, respectively. The structure of 6beta was established by its conversion into 2,3,4,6-tetra-O-acetyl-1-O-[1-methyl N-(tert-butyloxycarbonyl)-L-glutam-5-oyl]-beta-D-glucopyranose (7beta), whereas similar treatment of 6alpha gave a mixture of 1,3,4,6-tetra-O-acetyl-2-O-[1-methyl N-(tert-butyloxycarbonyl)-L-glutam-5-oyl]-alpha-D-glucopyranose (9) and 7alpha. A 1 leads to 2 acyl migration occurred during esterification of the aglycon carboxyl group of 6alpha with diazomethane to give 2-O-[1-methyl N-(tert-butyloxycarbonyl)-L-glutam-5-oyl]-alpha-D-glucopyranose (8).     

The effect of temperature and crowding on midgut amylolytic activity in Tenebrio molitor adults

The effect of two constant temperatures (23°C and 28°C), mixed group (5 + 5), and isolation on the midgut amylolytic activity during adult development of Tenebrio molitor has been investigated in vitro. Higher temperatures (28°C) and mixed groups stimulate the rate of midgut amylolytic activity. After attaining the maximal level, the amylolytic activity shows fluctuations. The possible role of hormones and primer pheromones in the control of the midgut amylolytic activity in T. molitor adults is discussed.     

A combined scanning and transmission electron microscopic study and electron probe microanalysis of human pineal acervuli

Summary Untreated, decalcified and trypsinized acervuli from human pineal bodies were studied with the scanning and transmission electron microscope as well as by electron probe microanalysis. The mulberry-like acervuli are composed of a various number of spherical lobes (135–800 m) between which clustered groups of globuli (4–14 urn in diameter) are observed. The acervular lobes are very probably formed by an aggregation of these globuli. Small round particles 125–500 Å in diameter are observed on the surface of the pineal concretions. These are not influenced by either decalcification or trypsin treatment. The acervular mineral corresponds morphologically to hydroxyapatite. The electron probe microanalysis reveals the existence of calcium and phosphorus as main components of the acervuli. Small quantities of magnesium and strontium were also detected.Dedicated to Professor Berta Scharrer on the occasion of her 70th birthdayWith the technical assistance of Mr. P.A. MilliquetThe author wishes to thank Mr. Bauer and Mr. Fryder (Nestec SA, La Tour de Peilz) for the use of the Cambridge Stereoscan electron microscope and Dr. T. Jalanti (C.M.E., Lausanne) for his help with the use of the X-ray microanalyser     

The role of immune pig colostrum,serum and immunoglobulins IgG,IgM, and IgA in local intestinal immunity against enterotoxic strain ofEscherichia coli 055 in germfree piglets

The protective effect of pig immune colostrum, serum and immunoglobulins IgG, IgM and IgA against the enterotoxic strain ofEscherichia coli O55, was studied in newborn germfree piglets. This strain produced accumulation of fluid and dilatation of intestine when injected into the ligated ileal segment of germfree piglets, which is considered to be the typical effect of enterotoxins. Erosion of the intestinal epithelium and penetration of bacteria into the submucosa were also observed. Immune serum, colostrum and all the immunoglobulin classes used produced a local protective effect, IgA being most effective. The mechanism of protection conferred by these immunoglobulins is discussed with respect to the possible pathogenic action of enterotoxicEscherichia coli O55 in the intestinal tract of immunologically virgin germfree piglets.