SUMMARY: The growth of nine strains of was assessed quantitatively by culture on Trypticase Soy/yeast extract/Tween 80 agar (TSY-TW) with and without supplementation with iron or haematin and on blood agar, in aerobic, reduced O (3% O with 8% CO, 8% H and 81% N) and anaerobic atmospheres. All strains grew better anaerobically and under reduced O conditions than aerobically on supplemented or unsupplemented TSY-TW. Supplementation of TSY-TW with iron or haematin resulted in an average 4·4-fold increase in bacterial count in a reduced O atmosphere and an average 4·2-fold increase under anaerobic conditions. Under aerobic conditions the increase in count ranged from 0 to >5000-fold, as some strains failed to grow on unsupplemented TSY-TW but responded well to the supplements of iron or haematin. The highest bacterial counts were obtained on Columbia blood agar incubated anaerobically. However, failed to grow aerobically on plain or heated Columbia blood agar with or without supplements. TSY-TW blood agar supported the growth of the one strain tested under all three atmospheric conditions. The type strain (ATCC 14953) differed from all others in its failure to grow aerobically or in a reduced O atmosphere on supplemented or unsupplemented media. Colony size varied greatly on different media, in different atmospheres and from strain to strain, being greatest in a reduced O atmosphere on Columbia blood agar. There was no correlation between the viable bacterial count and colony size.


Article metrics loading...

Loading full text...

Full text loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error