a major problem in dairy cows and beef cattle causing significant economic losses worldwide. Lesions are typically found at the volar skin proximal to the heel bulbs. Microscopic examination of biopsies or touch preparations of these lesions revealed a variety of different bacterial morphotypes including significant numbers of spirochetes which often represent the predominant morphotype. We used comparative 16s rRNA sequence analysis to determine the diversity and phylogeny of these hitherto unclassified DD spirochetes. Results indicate that those lesions looked at so far contained at least five spirochetal phylotypes, all clustering within the genus Treponema. Phylotype DDKL-4 was nearly identical (99.4% similarity) to that of a nonpathogenic human treponeme, T. phagedenis. Two phylotypes DDKL-3 and DDKL-13 were closely related to those from treponemes commonly found in human periodontitis lesions, i.e., T. denticoh and T. vincentii, exhibiting 95 and 98% similarity, respectively. The other two phylotypes, DDKL-12 and DDKL-20, had no close relatives to any cultivable treponemal species but clustered to previously described group IV oral treponemes. Preliminary analysis using in situ hybridization with fluorescently labeled oligonucleotide probes against smears from DD biopsies revealed that from all lesions analyzed so far, T. denticoh-like spirochetes were detected in the highest proportion of all spirochetal morphotypes.Digital dermatitis (DD), first described by Cheli and Mortellaro (6), is an acute or chronic ulcerative epidermitis in cattle that most commonly affects the skin immediately above the coronet between the heel bulbs (4). It is characterized clinically by an erosion of the superficial layers of the epidermis due to the loss of keratin, epithelial hyperplasia and hypertrophy, pain and swelling at the diseased sites, and a typical foul odor. Early lesions often show granulomatous strawberry-like ulcerations, whereas older lesions exhibit a grayish-brown color. DD usually leads to lameness and to a significant decrease in body weight and milk production (4). The disease is found with an incidence varying from 5 to 60% and a prevalence of 2 to 30%, rising to 80% in some herds and causing substantial economic loss in cattle dairies and the meat industry worldwide (38).Microscopic analysis of specimens taken from DD lesions revealed a variety of different bacterial morphotypes, including gram-negative rods and spirochetes. Spirochetes are often found in great numbers not only in superficial lesions but also in deeper layers of the dermis (5, 11,25). The etiology of DD is not yet established. However, the presence of high numbers of bacteria, including spirochetes, which apparently invade deeper tissues as well as successful antibiotic therapy strongly suggests a role of bacteria in the etioloLy of the disease (25). So far only a few organisms belonging to the genera Prevotella, Porphyromonas, Fusobacterium, and Bacteroides have been isolated (23). A recent paper reported the isolation of two groups of...

A novel Treponema species was isolated from an ulcerative lesion of a cow suffering from digital dermatitis (DD), a disease which causes painful ulcerations along the coronary band. Among other anaerobic bacteria, high numbers of spirochaetes have been regularly found in DD lesions. Here data are presented of a spirochaete isolated from a DD ulcer. By chemotaxonomy, protein analysis and comparative 165 rDNA sequence analysis this isolate was classified as a treponeme that differed from all Treponema species described previously. The only isolate, DD5/3l, for which the name Treponema brennaborense is proposed, is designated the type strain of the novel species.The strain is a small, highly motile spirochaete that has two periplasmic flagella, one flagellum being attached at each cell pole. Strain DD5/3f exhibits a-glucosidase and N-acetyl-p-glucosaminidase activity and growth is inhibited by rabbit serum. T. brennaborense was phylogenetically most closely related (89.5 O/ O 165 rRNA similarity) to Treponema maltophilum, an oral spirochaete isolated from a periodontitis patient.

Thin (3 nm) flexible fimbriae are shown which are mannose-resistent in hemagglutination. They were found on 35 strains of Salmonella typhimurium inclusively variatio Copenhagen, specific for pigeons, which were isolated from clinical cases of Salmonellosis. These thin fimbriae as lectins are of interest for adhesion to the intestine. Unlike the type 1 fimbriae (7nm) they don't need mannose as receptor on the cell membrane.

Unsymmetrical molecular interactions cause curvature in the double layers (depicted below) that arise from the crystallization from CHCl3 of the title enantiomer prepared by allylboration. Platelets without curvature are formed from the corresponding racemate. The curvature of these naturally occurring tubes thus depends on the chirality of the building blocks. Furthermore, the only piece of evidence for the chirality of the natural compounds comes from the curvature of its bilayer crystals.

Summary In the electron microscope an additional layer (glycocalix) of the cell wall and fimbriae on Haemophilus parasuis were shown in thin sections of the infected CAM which have their origin on the CM of the Haemophilus parasuis‐cells. No fimbriation was seen after conventional cultivation.