ヒト型結核菌H₃₇Rv株由来の混晶性タンパク質

抄録

Proteinic substances were separated as needle crystals from unheated culture filtrate of the strain H₃₇Rv of Mycobacterium tuberculosis grown in Sauton medium by saturated ammonium sulfate following fractionation with starch blook zone electrophoresis.
(1) Crystals of the same appearance were also found in the extract from surface large of the bacilli of M. tuberculosis and in culture filtrate of the strain ATCC 14468 of M. smegmatis. Proskauer Beck medium could be substituted for Sauton medium and Pevikon used instead of starch for supporting medium of the zone electrophoresis.
(2) The crystals were not separated in a particular fraction with saturated ammonium sulfate, but the concentration at 60% was of the best condition. Crystallization occurred in broad areas ranging from pH 2 to pH 9.
(3) Proteinic crystal was found to consist of pleural proteins and referred to as Mixed Crystal Tuberculoprotein (MCTP). MCTP separated from 0-50% SAS fraction was composed of α, β and other proteins, and in contrast, that from 50-70% SAS fraction β and other proteins.
(4) A glycoprotein associated with MCTP was detected from culture filtrate of M. tuberculosis, and separated by gel filtration using a Sephadex G-100, ion exchange chromatography with a DEAE sephadex A-25 as well as affinity chromatography with the aid of a Con A sepharose. This glycoprotein was assumed to form the nucleus of crystals.
(5) In addition of MCTP, an extracellular protein other than α and β antigens, named γ antigen, was separated and purified from culture filtrate of M. tuberculosis. The distribution of γ antigen was examined by the Ouchterlony's method. It was demonstrated in M. tuberculosis, including resistant strains against various drugs, and M. bovis, but not in M. kansasii, M. inarinum, M. scrofulaceuni, M. intracellulare-aviuin complex, M. fortuitum, M. chelonei and M. smegmatis.
According to, the authers' further investigation, it seems better to replace the term “crystal” with “paracrystals”.