Chloramphenicol resistance

Resistance to chloramphenicol is most commonly mediated by the enzymatic modification and inactivation of the antimicrobial agent, as a result of the action of chloramphenicol acetyltransferase (CAT). This enzyme catalyses the transfer of an acetyl group from acetyl coenzyme A to the primary hydroxyl group of chloramphenicol.28 The acetylated chloramphenicol derivatives do not bind to bacterial ribosomes and consequently do not exhibit antimicrobial activity. Many CAT enzymes have been...

Traumatic gas gangrene

The first symptom is usually sudden onset of severe pain at the site of surgery or trauma.2'4 The mean incubation period is less than 24 h, but ranges from 6 to 8 h to several days, probably depending on the degree of contamination and the extent of vascular compromise. The skin may initially appear pale, but quickly changes to bronze and then purplish red, and becomes tense and exquisitely tender. Bullae develop, which may be clear, red, blue, or purple. Gas in tissue may be detected by soft...

Clinical aspects

Tetanus may be either localized or generalized, the latter being more common. The incubation period typically is 2-14 days, but may be as long as several months after the injury. In generalized tetanus, trismus (masseter muscle spasm, or lockjaw) is the presenting symptom in about half the cases. Headache, restlessness and irritability are early symptoms, often followed by stiffness, difficulty chewing, dysphagia and neck muscle spasm. The so-called sardonic smile of tetanus (risus sardonicus)...

Brief Overview Of The Phylogenetic Structure Of The Genus Clostridium

Almost complete 16S rRNA DNA sequences have been determined for about 100 of the 120 validly described species of the genus Clostridium. This enormous progress was only made possible by the introduction of polymerase chain reaction (PCR)-mediated amplification of the gene coding for the 16S rRNA.12-18 The compilation of data by Collins et al.12 and recent updates in the ARB ('A software environment for sequence data') program (retrievable from arb mikro.biologie.tu-muenchen.de) demonstrate the...

References

Finegold S.M. (1977) Anaerobic Bacteria in Human Disease. Academic Press, New York. 2. Gill D.M. (1982) Bacterial toxins table of lethal amounts. Microbiol Rev 46 86-94. 3. Franz D.R., Pitt L.M. Clayton M.A., Hanes M.A. and Rose K.J. (1993) Efficacy of prophylactic and therapeutic administration of antitoxin for inhalation botulism. In DasGupta B.R. (ed.), Botulinum and Tetanus Neurotoxins Neurotransmission and Biomedical Aspects, pp. 473-476. Plenum, New York. 4. Montecucco C. and Schiavo G....

Clinical manifestations

Because botulinum toxin is hematogenously distributed and because relative blood flow and density of innervation are greatest in the bulbar musculature, all three forms of botulism manifest clinically as a symmetrical flaccid paralysis that first affects and descends from the muscles of the head, face, mouth and throat. It is not possible to have botulism without having bulbar palsies, yet in infants symptoms such as poor feeding, weak suck, feeble cry, drooling and even obstructive apnea are...

Molecular Regulation Of Sporulation

It has long been suggested that the sporulation processes in Bacillus spp. and Clostridium spp. share similar molecular mechanisms. Nevertheless, little attention has been paid to the genetic analysis of the latter, despite its considerable biotechnical potential.39'40 In Bacillus spp. phosphorylation of the regulatory protein SpoOA controls the initiation of sporulation and also changes in gene expression that occur during transition into stationary phase.41'42 Homologues of the B. subtilus...

JG Songer G Prophylaxis and therapy

Clostridium perfringens is susceptible to many antimicrobials, and prophylaxis in swine has been achieved by use of bacitracin,118 lincomycin, and others and in chickens with virginiamycin, tylosin, and bacitracin.46119-121 Neither antimicrobial agents nor hyperimmune serum has much therapeutic value, because death quickly follows the onset of clinical signs.122 Commercial vaccines against C. perfringens infection are often multivalent, typically consisting of inactivated cells, toxoids, or...

Clostridium Perfringens Type C Enteritis A Backgroundepidemiology

Infection with C. perfringens type C has been linked to a unique syndrome of segmental necrotizing enteritis of the proximal small intestine and has been locally referred to as 'Darmbrand' (or 'fire-bowels') in Germany where outbreaks occurred in the post-World War II period and as 'pigbel' in Papua New Guinea where it was originally associated with ritual pork feasts.81'82 Several lines of evidence have implicated the (3-toxin produced by C. perfringens type C as the primary virulence factor...

The conjugative tetracycline resistance transposon Tn5397 from Clostridium difficile

The C. difficile isolate that carries Tn5398, strain 630, also carries a second conjugative transposon, Tn5397, which encodes a iei(M)-like tetracycline resistance determinant and which is transferred independently of TnJ.398.1,23 25,27,69 Hybridization studies showed that at least six out of seven internal or junction fragments of Tn97< 5, representing 95 of its length, hybridized with Tn5397.25 These findings were confirmed by Mullany et al.26 who cloned the ief(M) gene and some of the...

In Vitro Sporulation

Although sporulation generally is initiated by a lack of nutrients, Clostridia need an energy source for macromolecular synthesis during sporulation and the cells may die if one or more nutrients are completely absent. However, not all Clostridium species can sporulate well in laboratory media because conditions for their sporulation can be highly specific. For example, Clostridium cellulo-lyticum sporulates following cellobiose starvation. A level of 30 sporulation occurs if cells are starved...

Clostridium Tetani

Spores of Clostridium tetani are introduced to animal hosts, usually traumati-cally, where they germinate (Table 10.2)280'281 and produce a neurotoxin which is responsible for all or most of the symptoms of tetanus. Soil is the usual source of C. tetani spores, especially soil rich in animal manure. Vegetative cells and spores are frequently detected in the digestive tract of animals, including cattle, horses, sheep, dogs, chickens, rats, guinea pigs, and humans.282 Susceptibility to tetanus...

Clostridium Haemolyticum

Clostridium haemolyticum is often referred to as C. novyi type D Table 10.2 .233,234 Phenotypically, it resembles type B,235 with the exception that it produces no a-toxin and much more P-toxin than type B strains. The organism can be found in soil,236'237 and ingestion leads to deposition of spores or vegetative cells in the digestive tract and liver. Under appropriate conditions, C. haemolyticum-induced disease, called bacillary hemoglobinuria, can develop. Bacillary hemoglobinuria occurs in...