Abstract
This report is to describe the condition for the occurrence of significantly remarkable and non-exceptional elongation of M. lepraemurium in vitro. The M. lepraemurium used was the Hawaiian strain. The culture medium, which was referred to as NK medium, was the Kirchner medium enriched with 0.25% glucose, 0.25% pyruvate, and 7.5% suc- rose, which was added bovine serum and α-ketoglutaric acid at the final concentration of 10% or 20% and 0.1%, respectively.
When the bacilli were cultivated for 10, 20, and 30 days at 30°C, the bacilli gradually elongated to 4.5, 6.5 and 8.9μm respectively from the initial length of 2.3μm, in the case of the NK medium containing 20% bovine serum. It was decided that the optimal concentration of α-ketoglutaric acid for adding to the EK medium was 0.1% at the final concentration. Furthermore, it was determined that this remarkable elongation phe-nomenon of the bacilli in the NK medium was not due to acidity of the medium result-ed from the addition of α-ketoglutaric acid, but the specific effect of α-ketoglutaric acid.
