Determination of Some in vitro Growth Requirements of Bacteroides nodosus

Abstract

SUMMARYPhysical and nutritional factors required for growth of Bacteroides nodosus isolates from ovine foot-rot lesions were examined. Simplified anaerobic culture techniques were devised utilizing a fully soluble, autoclavable, liquid medium (TAS) which contained proteose-peptone, yeast and meat extracts and certain other essential compounds required to promote prompt and serially transferrable growth of cultures from small inocula. The latter included Trypticase, arginine, a reducing agent (most suitably thioglycollic acid) and CO,; serine and Mg2+ markedly increased growth yields. Trypticase could not be replaced by a commercial preparation of acid-hydrolysed casein; other forms of hydrolysed proteins gave delayed and inconsistent growth. Maximum growth of cultures required concentrations of 0.02 to 0.05 M-arginine, which could not be replaced by glutamic acid, citrulline or ornithine. Exogenous carbohydrate compounds were not required.The temperature range for optimum growth of cultures was 37 to 39 "C, and anaerobic culture conditions were essential for growth and the production of B. i i~d o s i i s organisms of normal morphology. Solidified TAS media for the isolation and maintenance of B. nodosus cultures were also devised.

Type IV Fimbrial Biogenesis Is Required for Protease Secretion and Natural Transformation inDichelobacter nodosus

“…When required, media were supplemented with the following antibiotics at the indicated concentrations: for E. coli, ampicillin, 100 g/ml; erythromycin, 150 g/ml; kanamycin, 20 g/ml; and tetracycline, 10 g/ml; and for D. nodosus, erythromycin, 1 g/ml; tetracycline, 1 g/ml; and kanamycin, 10 g/ml. D. nodosus cells used for azocasein assays, transmission electron microscopy, twitching motility assays, elastase assays, and protease zymograms were grown in TAS media (71). DNA manipulations and molecular techniques.…”

Purification of Pili from Bacteroides nodosus and an Examination of their Chemical, Physical and Serological Properties

“…The Bacteroides nodosus strains studied included two New Zealand isolates (strains 91B and 80) and one from Australia (strain 198). The organisms were grown anaerobically in TAS liquid medium as described by Skerman (1975). The number of subcultures was kept to a minimum to preclude selection of variant organisms which produce low yields of pili (Stewart, 1973;Short et al, 1976 …”

A gene region in Dichelobacter nodosus encoding a lipopolysaccharide epitope

“…E. coli strains were grown on 2YT medium (Vieira & Messing, 1982) supplemented with 100 or 250 pg ampicillin ml-' where appropriate. D. nodosus reference strain A198 (Dewhirst et al, 1990) was cultured using Hoof (Thomas, 1958) or trypticase-arginine-serine (Skerman, 1975) medium in an environment of N2/H2/C02(80: 10: 10, by vol.). All of the E. coli host strains and plasmids used in this study are described in Table 1.…”