Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0519030 (Klebsiella)
 21,988 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cell free preparations of the whole-cell lysate and ultrafiltration (UF) fractions of broth cultures of a strain of Enterobacter cloacae, isolated from a Puerto Rican with tropical sprue, were assayed for their ability to induce in vivo net water secretion in the rat jejunum. The whole-cell lysate and UM-10 retentate of broth cultures were inactive. The UM-2 retentate and filtrate were active at a concentration of 100 mug/ml or more; the toxigenic activity was entirely retained, and increased to 1 mug/ml, by a UM-05 membrane; washing this retentate yielded a fraction with an activity of 10 ng/ml. Stationary aerobic culture conditions yielded the most active UF fractions when ammonium sulfate was used as the precipitating agent, whereas anaerobic culture conditions produced the most active fractions in broth cultures precipitated by acetone. Passage of the active acetone-precipitated UF fractions through a Sephadex G-25 column yielded eluate pools with enhanced toxigenic activity in, or adjacent to, the void volume, but maximum activity of the ammonium sulfate-precipitated UM-05 retentate eluated at a Kav of 0.38 to 0.52. Neither of the most active gel filtration elution fractions of the UM-05 retentates contained detectable carbohydrate, suggesting that the toxin is not associated with endotoxin. Toxigenic activity was unaltered by exposure to a temperature of 100C for 30 min, lowering the pH to 1, or incubation with either Pronase or trypsin. These observations indicate that the strain of E. cloacae under study elaborates a heat-stable enterotoxin htat has approximately the same molecular weight and shares many of the characteristics of the heat-stable enterotoxin produced by some strains of Escherichia coli and Klebsiella pneumoniae.
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PMID:Partial purification and properties of Enterobacter cloacae heat-stable enterotoxin. 0 76

The enterotoxigenicity of strains of Klebsiella pneumoniae, Enterobacter cloacae, and Escherichia coli, which represented the predominant coliform species isolated from the jejunum of 12 patients with tropical sprue and 5 with the blind-loop syndrome, was quantitatively assessed in terms of the ability of toxin preparations to induce water secretion as assayed by in-vivo perfusion in the rat jejunum. All 12 patients with sprue harboured 1 or more highly toxigenic strains--14 of the 16 strains isolated from this group produced heat-labile and/or heat-stable toxins which were as potent as toxins derived from strains isolated from persons with acute diarrhoea and documented as toxigenic. None of the 9 strains isolated from patients with the blind-loop syndrome produced potent toxins. This difference between the coliform bacteria in sprue and the blind-loop syndrome probably accounts, at least partly, for the different intestinal response in these two disorders to contamination by these organisms.
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PMID:Enterotoxigenicity of colonising coliform bacteria in tropical sprue and blind-loop syndrome. 7 10

The effects on intestinal transport of either a semipurified preparation of enterotoxin elaborated by Klebsiella pneumoniae or similaryly prepared control material were tested by marker perfusion studies in the small intestine of rats. At a concentration of 2 mg/ml, the enterotoxin produced net secretion of water, Na, and Cl in both jejunal and ileal segments; HCO3 transport was not affected. Net secretion was evident within 30 min after intorduction of the toxin and was maximal after 90 min. The addition of 56 mM glucose to the enterotoxin-containing perfusion fluid resulted in reversal of water and Na transport to net absorption in both intestinal segments. The enterotoxin also produced a significant depression of xylose absorption in both the jejunum and ileum but did not affect the absorption of either glucose or L-leucine. Intestinal structure was not altered after perfusion of the toxin but insillation of approximately one-quarter of the total perfusion dose into a ligated jejunal loop for 18 h produced fluid secretion and structural abnormalities. These observations confirm the fact that other species of coliform bacteria in addition to tescherichia coli are capable of elaborating an enterotoxin. Such species commonly contaminate the small intestine of persons with tropical sprue and it is suggested that chronic exposure of the intestinal mucosa to the enterotoxin elaborated by these bacteria may be a factor in the pathogenesis of intestinal abnormalities in thid disorder.
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PMID:Effect of Klebsiella pneumoniae enterotoxin on intestinal transport in the rat. 16 97

The enterotoxigenicity of 12 strains of coliform bacteria (Enterobacter cloacae, Klebsiella pneumoniae, and Escherichia coli) isolated from the gastrointestinal (GI) tract of persons with either acute diarrhea or tropical sprue and of 13 strains of the same species isolated from urine (GU) cultures was determined. Fractions of heat-labile (LT) and heat-stable (ST) toxins of each strain were separated by ultrafiltration, and the effect of graded concentrations (range, 100 microgram-10 pg/ml) on water transport was assessed by in vivo perfusion in the rat jejunum. Enterotoxigenic activity was defined as inducement of net secretion of water. All 12 of the GI strains and six of 13 GU strains elaborated enterotoxins, but there was a millionfold quantitative difference in the potency of the toxins produced. All of the GI strains produced one or both forms of toxin, which had a minimal effective concentration of as low as 0.1-10 ng/ml, whereas the GU strains produced toxins of weak or, rarely, of intermediate potency.
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PMID:Relative enterotoxigenicity of coliform bacteria. 33 Jul 67

Coliform bacteria were isolated by either aerobic or anaerobic culture techniques from aspirates of the proximal small intestine of 4 of 5 Haitians with tropical sprue, but not from any of 10 well nourished Haitians who had milder gastrointestinal complaints and abnormalities. Klebsiella (Klebsiella pneumoniae and Klebsiella ozaenae) was cultured from the jejunal aspirates of 2 sprue patients and Escherichiae coli from the other 2. Fifteen colonies of coliform bacteria cultured from each aspirate were specifically identified by their biotype. In three instances, every colony in each aspirate was the same; In three instances, every colony in each aspirate was the same; in the fourth aspirate, two biotypes of E. coli were present, one of which grew under both aerobic and anaerobic culture conditions and another which grew only under anaerobic conditions on initial isolation. A randomly selected strain of each of the five coliform biotypes isolated was examined for enterotoxigenicity by determining the effect of variously prepared cell-free preparations on water transport in the rat jejunum using standard marker perfusion techniques. Every strain tested was toxigenic; one produced only a heat-stable toxin, one produced a heat-labile toxin only, and three elaborated both forms of enterotoxin. These observations indicate that most Haitians with tropical sprue have colonization of the proximal small intestine by a specific strain of enterotoxigenic coliform bacteria, but such is not the case among Haitians who have milder intestinal abnormalities.
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PMID:Contamination of the small intestine by enterotoxigenic coliform bacteria among the rural population of Haiti. 77 37

The factors responsible for colonization of the small intestine by enterotoxigenic coliform bacteria in Puerto Ricans with tropical sprue are unknown, but epidemiological observations have suggested that they may be related to an increased dietary intake of long-chain unsaturated fatty acids, particularly linoleic acid, which is known to exert an inhibitory effect on the growth of gram-positive organisms that normally comprise the flora of the small intestine. We have examined, by using a glucose-limited continuous-culture system, what effect this fatty acid exerts on the growth relationships of enteric gram-positive and coliform bacteria. In this system, colonization by an invading strain of Klebsiella pneumoniae was prevented by the presence of an established culture of Lactobacillus acidophilus, principally by virtue of a lowered pH of the medium that was incompatible with Klebsiella growth. However, when the population density of L. acidophilus was reduced by the presence of a sufficient concentration of linoleic acid, the invading K. pneumoniae successfully colonized the system and, once established, suppressed the growth of L. acidophilus. These observations indicate that, under the conditions of our chemostat, gram-positive enteric bacteria suppress coliform growth and that this effect is reversible by the presence of linoleic acid. It remains to be established, however, what pertinence these in vitro observations have to conditions within the intestinal tract of persons living in the tropics.
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PMID:Enterotoxigenic intestinal bacteria in tropical sprue. IV. Effect of linoleic acid on growth interrelationships of Lactobacillus acidophilus and Klebsiella pneumoniae. 81 64