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immediate threats. In contrast, the innate immunity acts promptly by recognizing conserved and distinct molecular patterns of pathogens. But what strategy can be employed by the innate immunity to recognize bacterial toxins, most of which do not share common structures and are highly diverse and mutable? One possibility would be to produce effector molecules for each toxin class and target them based on their specific properties. However, an emergence of a new class of microbial toxins would leave eukaryotic hosts (whose evolution is much slower than that of microbes

J. Perinat. Med. 40 (2012) 73–76 • Copyright by Walter de Gruyter • Berlin • Boston. DOI 10.1515/JPM.2011.104 2011/0160 Article in press - uncorrected proof Parallel maternal and fetal immune activation by bacterial toxins in vitro* Bruce K. Young**, Xiao Li and Alan A. Arslan Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, New York University School of Medicine, New York, NY 10016, USA Abstract This study evaluated in vitro immune responses to Escheri- chia coli lipopolysaccharide in maternal and fetal blood. Samples were

3.5 Genetic Detoxification of Bacterial Toxins Rino Rappuoli and Mariagrazia Pizza 3.5.1 Introduction Serendipity often provokes discoveries and technological breakthroughs. A milestone in vaccine development was the discovery by Glenny and Ramon, that formalin treat- ment of a culture supernatant of Corynebacterium diphtheriae, renders it unable to kill guinea pigs, that became resistant to subsequent challenges with diphtheria tox- in (Ramon, 1924; Glenny and Hopkins, 1923). This observation made feasible the large scale detoxification of diphtheria and

Pure & App!. Chem., Vol. 59, No. 1 1, pp. 1477—1488, 1987. Printed in Great Britain. © 1987 IUPAC Glycolipids as attachment sites on animal cells for bacteria, bacterial toxins and viruses: aspects on identification and characteristics Karl-Anders Karisson Department of Medical Biochemistry, University of Gdteborg, P.O.Box 33031, S-400 33 GöTEBORG, Sweden Abstract - The abundance of glycoconjugates at the animal cell surface is a probable explanation why microbes appear to have selected primarily carbohydrates as essential at- tachment sites for normal

Determination of Exotoxin in Bacillus thuringiensis Cells K. Horská *, J, Vanková **, and K. Šebesta * Institute of Organic Chemistry and Biochemistry *, Czechoslovak Academy of Sciences, Prague and Institute of Entomology **, Czechoslovak Academy of Sciences, Prague (Z. Naturforsch. 30 c, 120 — 123 [1975]; received August 9, 1974) Exotoxin, B. thuringiensis, Bacterial Toxins The presence of exotoxin in Bacillus thuringiensis was demonstrated and its quantity in the cells determined. The concentration of exotoxin in the producing microorganism is approximately

Abstract

We estimated the usefulness of spore-crystals preparations of the two B. thuringiensis isolates, MPU B9 and MPU B54, for reducing the number of pests. The potential insecticidal toxicities of B. thuringiensis isolates were assessed by the analysis of the genes coding for crystalline proteins. The activities of spore-crystals preparations were determined against Dendrolimus pini L. (Lepidoptera: Lasiocampidae) and compared with the toxicity of spores and crystals of B. thuringiensis subsp. kurstaki HD-1 from commercial biopesticide Foray. Although the analysis of crystalline toxin gene profiles indicated potentially higher activities of MPU B9 and MPU B54 crystals against the pests than that of HD-1, the toxicities of isolate and HD-1 preparations against D. pini caterpillars were similar. The LC50 amounted to 3.42×104 spores and crystals for HD-1, 3.36×104 for MPU B9 and 3.5×104 for MPU B54. Additionally, the toxicity of the MPU B54 preparation was evaluated against Spodoptera exigua (Hubner) (Lepidoptera: Noctuidae). The LC50 was 4.5×105 spores and crystals of MPU B54, and 2.69×106 spores and crystals of HD-1. The LC50 of the MPU B54 preparation against S. exigua was approximately six-fold higher than that of HD-1. However, due to the very wide fiducidal limits for LC50 values, which for both preparations overlap to a large extent, the toxicity of the preparations should be considered the same. The varied profiles of crystalline toxin genes and important toxicity of spore-crystal mixtures of isolates against S. exigua and D. pini indicate the effectiveness of the mixtures against pests and make the strains an alternative for HD-1 for reducing the number of insects.

Subchronic exposure of rats to sublethal dose of microcystin-YR induces DNA damage in multiple organs

Background. Microcystins (MCs) are cyclic heptapeptides that are considered to be liver specific toxins. They are potent tumour promoters and recent studies indicate that they are also genotoxic. In this study we measured DNA damage in lymphocytes, liver, kidney (cortex and medulla), lung, spleen and brain cells of male Fisher F344 rats that were exposed to sublethal dose (every second day 10 μg/kg b.w.; i.p) of micro-cystin-YR (MCYR) for one month.

Methods. At the end of exposure the animals were sacrificed, the lymphocytes were isolated from blood taken from jugular vein, liver cells were obtained by perfusion with collagenase A and the cells from other organs were isolated by incubating small tissue pieces with collagenase A. The DNA damage in isolated cells was measured with the single cells gel electrophoresis (SCGE) also called the comet assay.

Results. A significant increase of the % tail DNA in MCYR-exposed animals compared to the nonexposed control ones was observed in brain (2.5 fold), liver (2.1 fold), kidney medulla (1.9 fold), kidney cortex (1.8 fold) and lung (1.7 fold) cells, while the DNA from lymphocytes and spleen cells was not affected.

Conclusion. This study demonstrated that subchronic exposure to sublethal doses of MCs can induce systemic genotoxicity in mammals, and it affects not only the liver but also other vital organs.

bacterial toxins and proteases O’Hanley et al . [ 17 ] used a mouse model with pyelonephritis. The results showed that a vaccine targeting the hole-forming toxin (A-type or alpha-hemolysin) of UPEC could delay the progression of renal injury. However, this vaccine did not prevent UPEC colonization in the kidneys. Meanwhile, the vaccine for proteus hemolysin A (HpmA) could not prevent the colonization of bacteria in the kidneys of mouse model with urinary tract infection. However, it targets a vaccine that can damage the bacterial toxin (Pta) of the endothelial cells

L E P T 0 S P 1 R A E AND THEIR TOXINS AND ANTISERA ON CHICK EMBRYO FIBROBLAST 563 The Influence of Leptospirae and their Toxins and Antisera on Chide Embryo Fibroblast and He-La Tissues J ozef P a r n a s * a n d H a l in a P ink iew ic z Academy of Medicine, Department of Microbiology, Lublin — Poland (Z. Naturforschg. 21 b, 563—566 [1966]; eingegangen am 24. Juli 1965) A number of investigators have examined the influence of different gram negative and gram positive bacteria upon various tissue cultures, as well as the effects of bacterial toxins and

Biol. Chem., Vol. 381, pp. 421–426, May/June 2000 · Copyright © by Walter de Gruyter · Berlin · New York Minireview Rho GTPases as Targets of Bacterial Protein Toxins Klaus Aktories*, Gudula Schmidt and Ingo Just Institut für Pharmakologie und Toxikologie der Universität Freiburg, Hermann-Herder-Str. 5, D-79104 Freiburg, Germany * Corresponding author Several bacterial toxins target Rho GTPases, which constitute molecular switches in several signaling processes and master regulators of the actin cyto- skeleton. The biological activities of Rho GTPases are