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11.
Wickerhamomyces anomalus killer strains are important for fighting pathogenic yeasts and for controlling harmful yeasts and bacteria in the food industry. Targeted disruption of key genes in β‐glucan synthesis of a sensitive Saccharomyces cerevisiae strain conferred resistance to the toxins of W. anomalus strains BS91, BCA15 and BCU24 isolated from olive brine. Competitive inhibition of the killing activities by laminarin and pustulan refer to β‐1,3‐ and β‐1,6‐glucans as the main primary toxin targets. The extracellular exoglucanase‐encoding genes WaEXG1 and WaEXG2 from the three strains were sequenced and were found to display noticeable similarities to those from known potent W. anomalus killer strains. Accession Nos for WaEXG1 genes for the strains in brackets are JQ734563 (BS91), JQ734564 (BCA15) and JQ734565 (BCU24); for WaEXG2 genes JQ734566 (BS91), JQ734567 (BCA15) and JQ734568 (BCU24), respectively. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
12.
Barbara P. Atshaves Avery L. McIntosh Stephen M. Storey Kerstin K. Landrock Ann B. Kier Friedhelm Schroeder 《Lipids》2010,45(2):97-110
Since liver fatty acid binding protein (L-FABP) facilitates uptake/oxidation of long-chain fatty acids in cultured transfected
cells and primary hepatocytes, loss of L-FABP was expected to exacerbate weight gain and/or obesity in response to high dietary
fat. Male and female wild-type (WT) and L-FABP gene-ablated mice, pair-fed a defined isocaloric control or high fat diet for
12 weeks, consumed equal amounts of food by weight and kcal. Male WT mice gained weight faster than their female WT counterparts
regardless of diet. L-FABP gene ablation enhanced weight gain more in female than male mice—an effect exacerbated by high
fat diet. Dual emission X-ray absorptiometry revealed high-fat fed male and female WT mice gained mostly fat tissue mass (FTM).
L-FABP gene ablation increased FTM in female, but not male, mice—an effect also exacerbated by high fat diet. Concomitantly,
L-FABP gene ablation decreased serum β-hydroxybutyrate in male and female mice fed the control diet and, even more so, on
the high-fat diet. Thus, L-FABP gene ablation decreased fat oxidation and sensitized all mice to weight gain as whole body
FTM and LTM—with the most gain observed in FTM of control vs high-fat fed female L-FABP null mice. Taken together, these results
indicate loss of L-FABP exacerbates weight gain and/or obesity in response to high dietary fat. 相似文献
13.
Although fatty acid-binding proteins (FABP) differentially affect fatty acid uptake, nothing is known regarding their role(s)
in determining cellular phospholipid levels and phospholipid fatty acid composition. The effects of liver (L)- and intestinal
(I)-FABP expression on these parameters were determined using stably transfected L-cells. Expression of L- and I-FABP increased
cellular total phospholipid mass (nmol/mg protein) 1.7- and 1.3-fold relative to controls, respectively. L-FABP expression
increased the masses of choline glycerophospholipids (ChoGpl) 1.5-fold, phosphatidylserine (PtdSer) 5.6-fold, ethanolamine
glycerophospholipids 1.4-fold, sphingomyelin 1.7-fold, and phosphatidylinositol 2.6-fold. In contrast, I-FABP expression only
increased the masses of ChoGpl and PtdSer, 1.2- and 3.1-fold, respectively. Surprisingly, both L- and I-FABP expression increased
ethanolamine plasmalogen mass 1.6- and 1.1-fold, respectively, while choline plasmalogen mass was increased 2.3- and 1.7-fold,
respectively. The increase in phospholipid levels resulted in dramatic 48 and 33% decreases in the cholesterol-to-phospholipid
ratio in L- and I-FABP expressing cells, respectively. L-FABP expression generally increased polyunsaturated fatty acids,
primarily by increasing 20∶4n−6 and 22∶6n−3, while decreasing 18∶1n−9 and 16∶1n−7. I-FABP expression generally increased only
20∶4n−6 proportions. Hence, expression of both I- and L-FABP differentially affected phospholipid mass, class composition,
and acyl chain composition. Although both proteins enhanced phospholipid synthesis, the effect of L-FABP was much greater,
consistent with previous work suggesting that these two FABP differentially affect lipid metabolism. 相似文献
14.
Major advances in understanding cholesterol dynamics and the role that cholesterol plays in vascular disease have recently
been made. The brain is an organ that is highly enriched in cholesterol, but progress toward understanding brain cholesterol
dynamics has been relatively limited. This review examines recent contributions to the understanding of brain cholesterol
dynamics, focusing on extracellular and intracellular lipid carrier proteins, membrane cholesterol domains, and emerging evidence
linking an association between cholesterol dynamics and Alzheimer's disease. 相似文献
15.
The conversion of a number of alcohols, ethers, ketones, aldehydes, carboxylic acids, esters, and cyclic compounds and their mixtures on H-ZSM-5 at 673 K was investigated. These compounds can be easily converted to aromatic hydrocarbons if the C/H ratio of the molecule fragment, remaining after elimination of oxygen as water, is less than 0.62. At higher C/H ratios, coking of the catalyst increases, thus reducing its lifetime, a difficulty which can be overcome by hydrogenation of these compounds prior to their conversion over H-ZSM-5. A procedure is proposed for converting at least a part of organic waste chemicals to valuable products instead of burning them. 相似文献
16.
17.
Foued Ameur Paul Fischer Klaus-U. Höffgen Friedhelm Meyer auf der Heide 《Acta Informatica》1996,33(7):621-630
A pac-learning algorithm is -space bounded, if it stores at most examples from the sample at any time. We characterize the -space learnable concept classes. For this purpose we introduce the compression parameter of a concept class and design our Trial and Error Learning Algorithm. We show : is -space learnable if and only if the compression parameter of is at most . This learning algorithm does not produce a hypothesis consistent with the whole sample as previous approaches e.g. by Floyd,
who presents consistent space bounded learning algorithms, but has to restrict herself to very special concept classes. On
the other hand our algorithm needs large samples; the compression parameter appears as exponent in the sample size. We present
several examples of polynomial time space bounded learnable concept classes: – all intersection closed concept classes with
finite VC–dimension. – convex -gons in . – halfspaces in . – unions of triangles in . We further relate the compression parameter to the VC–dimension, and discuss variants of this parameter.
Received May 24, 1994 / July 4, 1995 相似文献
18.
Auslagerungsversuche mit verschiedenen geschweißten und verspannten Proben aus den chromhaltigen austenitischen Manganstählen X 40 MnCrN 19 und X 12 MnCr 18 12 sowie dem chromfreien Stahl X 50 Mn 20 in Meerwasser der Nord- und Ostsee. Makroskopische und mikroskopische Beurteilung der Proben nach sechs Wochen, einem halben Jahr, einem Jahr und zwei Jahren hinsichtlich Beständigkeit gegen unterschiedliche Korrosionserscheinungen, besonders hinsichtlich transkristalliner Spannungsrißkorrosion. 相似文献
19.
20.
Friedhelm Meyer auf der Heide 《Theoretical computer science》1981,13(3):315-322
The number of pebbles used in the black [black-white] pebble game corresponds to the storage requirement of the deterministic [non-deterministic] evaluation of a straight line program. Suppose a distinguished vertex of a directed acyclic graph can be pebbled with k pebbles in the black-white pebble game. Then it can be pebbled with k′≤1/2k(k?1)+1 pebbles in the black pebble game. 相似文献