野口英世著

Journal of Experimental Medicine

所収論文

こ の PDF は Journal of Experimental Medicine に 掲 載 さ れ た 論 文 を Rockefeller
University Press の許可（2020 年 3 月 18 日付）を得てアップロードしています。

TREPONEMA MUCOSUM (NEW SPECIES), A MUCINPRODUCING SPIROCH2ETA FROM PYORRHEA
A L V E O L A R I S , G R O W N IN P U R E C U L T U R E . *BY HIDEYONOGUCHI,

M.D.

(From the Laboratories of The Rockefeller Institute for Medical Research..
New York.)

PLATE I8.
Pyorrhea alveolaris is generally regarded as the sequel to a pathological metabolism known as the uric acid diathesis. Whatever theprimary predisposing factors may be, the characteristic fetid odor
from the affected mouth betrays the presence of certain putrefactive
mlcro/Srganisms in the perialveolar tissues which surround theloosened roots o f the diseased teeth. The bacteriological studies
which, on account of the lack of cultural methods for most of theorganisms concerned, were necessarily limited to their morpholog'y,helped but little, for the varieties of the microbes therein found d(ynot differ greatly morphologically from those commonly seen in thegingival deposit on unclean teeth of individuals who do not havepyorrhea alveolaris. Most authorities mention the presence o f
Spiroch6eta buccalis, Trepone~na macrodentium, Treponemc~ microdentium, fusiform bacilli, and, occasionally, a spirillum allied to thatof Vincent. But which of these organisms is most responsible f o r
the fetid odor could not be determined for the reason that until very
recently neither the spiroch~et~e nor the other forms were isolated~in pure cultures.
The fusiform bacilli and spirilla of Vincent's type have been obtained in pure culture by Ellermann, 1 Weaver and Tunnicliff, ~Miihlens, 3 and others, 4 who found that these organisms produce thepeculiar fetid odor characteristic of pyorrhea alveolaris.
* Received for publication, May 15, 1912.
Ellermann, V., Centralbl. ft. Bacteriol., Orig., 19o4, xxxvii, 729.
2Weaver, G. H, and Tunnicliff, R., Your. Inflect. Dis., 19o5, ii, 446.
s Miihlens, P., Deutsch. reed. Wchnschr., 19o6, xxxii, 797.
*Tunnicliff, R., Jour. Infect. Dis., 19o6, iii,148.
194

Hideyo Noguchi.

195

Of the spiroch~etm, one medium type, Treponema macrodentium,and one small type, Treponema microdentium, have been cultivatedby me from non-pyorrheal cases,5 but the macrodentium produces noodor and the microdentium produces a putrefactive odor which issomewhat different in nature from that which comes from pyorrhea
alveolaris.
In the present communication I shall describe a small spiroch~eta
which was isolated from the pus derived from a case of pyorrhea
alveolaris. Morphologically the organism resembles greatly Treponema pallidum and Treponema microdentium, but it differs fromboth in several principal biological properties. Its most striking feature is its capacity to produce in pure culture a mucin and a strong
fetid odor. Since this species has, for the first time, been recognized
and isolated from other varieties, I propose for it the name Treponema mucosum. At present I shall not discuss the question of how
much this particular spiroch~eta contributes towards the productionof the fetid odor in the pyorrheal discharge, but I shall describe themethod of cultivation and its morphology and biology in pureculture.
Method of Cultivation.--The purulent discharge of pyorrheal
teeth is collected by means of a sterile capillary pipette and thensuspended in a few cubic centimeters of sterile citrate solution.
By means of a capillary pipette this emulsion is inoculated into a
number of tubes of solid culture media consisting of one part o f
ascitic fluid, two parts of ordinary agar,-and having a piece ofsterile fresh rabbit kidney at the bottom; the whole medium iscovered with a layer of sterile paraffin oil. The technique is thesame as that used for obtaining the pallidum or refringens from acontaminated chancre or condyloma. After inoculation the tubes
are incubated at 37 ° C. for about ten days. The whitish semitransparent growth may be seen to spread out from the stab canalwhich is now filled with a dense growth of various bacteria. The
tube is cut open at the middle, the freshly exposed surface of theagar column is carefully sterilized with a sublimate alcohol solution,
the moisture carefully wiped off and then the cloudy colony of thespirochmtm is reached by inserting a sterile capillary pipette t h r o u g hNoguchi, H., Jour. Exper. Meal., 1912, xv, 81.

i96

Treponema mucosum, Grown in Pure Culture.

the clean surface. A small portion of the colony is thus taken out
a n d transferred to a new medium. By repeating this process o f
purification one finally obtains a pure culture.
Properties of the Pure Cultures.--In the ascitic agar medium,
containing fresh sterile tissue, the colonies become visible withintwenty-four to forty-eight hours, and with the exception of theupper 1.5 centimeters the entire agar column is rendered unevenlyopalescent. The individual colonies are recognized as dense, whitish
turbidities of varying sizes concentrically arranged but having no
definite outer boundaries. In a rapidly growing culture the neighboring colonies unite with each other b y their gradually thinning
peripheries, thus making the whole tube quite opalescent, although
the original colonies still stand out more or less distinctly.
No gas is formed. The culture gives off a strong fetid odor thatis easily recognized at a distance. A f t e r growing for two or threeweeks the tissue in the culture becomes at first greyish and thenquite dark (similar changes were found in the microdentium culture). The culture now contains a varying amount of mucin.
When the media is broken up this is seen as an extremely fine string
stretching from one piece of agar to another. The mucin string is
not sticky, but draws out as a fine filament. I have seen no bacteria
which produce a similar mucin.
The organisms remain alive for several weeks in the same culture
at 37 ° C. The mucin-producing faculty has apparently sufferedthrough repeated transplantations and at present, in its sixteenth
generation within I6O days, the culture has almost lost this quality.
On the other hand, its capacity to produce a bad odor has in no wise
diminished.
Like other treponemata, the mucosum is an anaerobe and requires
the presence of serum constituents for its growth. It grows welt
without the presence of fresh tissue. The fluid medium is mademarkedly opalescent without forming a definite coagulum. In thisfluid medium t h e growth produces a very strong odor.
Morphologically Treponema mucosum resembles both the pallidum and the microdentium, measuring on the average 8 to I2
microns by 0.25 to 0. 3 of a micron (figures I and 2, Treponema
mucosum; figures 3 and 4, Treponema microdentium; figures 5 andHideyo Noguchi.

197

6, Treponema pallidum). The number of curves varies from sixto eight. These curves are remarkably regular and are often quite
deep. Both extremities are sharply pointed and often possess atone or b o t h ends a fine, minutely curved projection that varies i nlength in different organisms. The length of this projection may
reach eight to ten microns. The organisms show a gracefulr o t a t i n g movement, and are often seen joined to each other by athin filament forming a pair, or chain of three, four, or more individuals. Under certain cultural conditions forms suggestive of alongitudinal division are observed.
When cultivated under unfavorable conditions a large number ofirregular forms appear. Some of these are almost straight and someare slightly or irregularly cilrved. There are also many granularparticles. These particles may be merely degenerative products orthey may be segments which under favorable conditions are capableof reproducing the spiroch~et~e. These segments or granules takethe chromatin stain and vary in size. Not infrequently a longspiroch~eta is found undergoing a granular segmentation (degeneration?), or a small spirochmta is seen attached to a round body as if
it had just sprouted out of the latter. In its staining reactions themucosum behaves as the microdentium does and takes the red in theGiem~a stain.
Pathogenicity.--When a large quantity of active fluid culture isinoculated into the cutaneous tissue of the skin of a Macacus rhesus
monkey, it produces an acute inflammation and the tissues remain
indurated for one week or ten days: There is no tendency to suppuration, and after twenty-four hours the tissue does not containliving spiroch~et~e. In the testicular tissue of rabbits the inoculatedorganisms produce also a marked induration (acute inflammatory)
which may last for one week, but no abscess formation was observed.
The testicle returns to its normal appearance in about two weeks.
When a culture in ascitic agar (as an emulsion) is inoculated, thetesticle becomes intensely inflamed within twenty-four hours andremains so for nearly ten days. The inflammation then graduallysubsides, but the hard circumscribed nodule persists for many weeks.
When the testicle is punctured with a capillary pipette.a yellowish
thick pus flows out. This pus has a fetid odor and in it a small

198

Yreponema mucosum, Grown in Pure Culture.

number of the spirocha~t~e are still to be seen. By transplanting thepus into a new culture medium a pure growth of this organism canbe obtained. F r o m this fact it seems that the mucosum can survive
in the testicle of rabbits when there is simultaneously introduced aforeign substance (agar), but not without the aid of the latter;hence it is not an independent parasite.
Differentiation f r o m the Allied Species.--The mucosum differsfrom the mierodentium in producing a mucin, a stronger fetid odor,a denser growth, and in surviving in the rabbit testicle when in,
troduced with agar. Morphologically it is almost impossible todifferentiate these two species. The pallidum differs from thisorganism by its pathogenicity, by producing no odor or mucin, by
its fainter diffuse growth, and by r~quiring for its growth thepresence of fresh tissue in the m e d i a .
CONCLUSIONS.

I. A mucin-producing spiroch~eta has been obtained in pure culture from a case of pyorrhea alveolaris. This organism is an independent species of the genus Treponema and, as it is recognized forthe first time, I propose for it the name Treponema mucosum.
2. Morphologically the mucosum is difficult to separate from thepallidum and microdentium, but, through its biological properties
and animal reactions it is easily differentiated from all the rest of
the spiroch~et~e.
3. The mucosum is not parasitic in the strict sense of the term, but
exerts a certain pyogenous action when the tissue has been so injured
by foreign substances as to enable it to survive.
4- The strong fetid odor in the discharge from pyorrhea alveolaris is due, at least in part, to the presence of the mucosum in theaffected tissue.
EXPLANATION OF PLATE I8.
Dark-field views of the organisms. X I,Ioo.
FIGS. I and 2. Treponema mucosum from pure cultures ten days old.
FIGS. 3 and 4. Treponema microdentium from pure cultures ten days 01d.
FIGS. 5 and 6. Treponema pallidum from pure cultures two weeks old.

T H E JOURNAL OF EXPERIMENTAL MEDICINE VOL. XVI.

PLATE 18.