noticed that the young nodules initially began looking as though they contained
rod-shaped bacteria. And, although early in their development it was the bacteroid
structures which contained those things which looked like small bacteria, eventually
the bacteroids developed into something which contained no resemblance to
bacteria.
Brunchorst believed that rather than actual bacteria being involved in the bacteroids, the bacteroids were natural formations and normal organs that play a role in
the plant’s substance balance. By my translation, I would quote Brunchorst as stating
“If one assumes such activity of the bacteroids, it cannot be astonishing that they
approach the real organisms [bacteria], in appearance and chemical behavior in such
a way that they have so far been confused with them, while their development and
their dissolution [of the bacteroids] at the end of the vegetation [plants life cycle], as
set out above, shows that they are structures of the plasma of the legumes themselves
whose similar physiological function leads indeed [to a] most morphological resemblance to bacteria. After all, it is a very interesting case that the plasma of higher
plant cells can take on such a microorganism-like shape.”
Brunchorst similarly thought there was no reason to regard the bacteroids as
being either fungal spores or fungal organs. By my translation, I would quote
Brunchorst as stating “On the other hand, it is undoubted that, as Frank [presumably
Albert Bernhard Frank] says, they [the bacteroids] are actually surrounded by a
membrane” and that “This alone would make it unlikely that you would have
mushroom galls in front of you in the nodules”. Brunchorst further believed that
his findings, again by my translation “... force us to assume that we have it in the
nodules to be normal organs of the legumes, the bacteroids have to do with equally
normal organs of the cell plasma. It must always be noted what is beyond all doubt
that the nodules are only there for the bacteroids, only because of them [the
bacteroids, do the nodules] have a right to exist.”
Thusly, although Brunchorst used the word ‘symbiose’ in reference to the root
nodules, and Brunchorst is credited for establishing a hypothesis that a symbiosis
takes place through and in the nodules, he believed it was a symbiosis between the
legume and a fungus and that this symbiosis had nothing to do with the bacteroids.
Brunchorst believed that the nodules were organs which gave legumes an ability to
utilize any nitrogen-containing organic matter in the soil. Brunchorst developed his
opinion after studying Lupinus luteus, Trifolium pratense, Vicia sativa, and a few
other legume species. The plant group previously known as Leguminosae we now
consider to be Fabaceae. Microbiologists have since kept the term bacteroid. We also
have come to know that root nodule cells contain symbiosomes which enclose the
bacteria.
14 Discovering the Symbiotic Nature of Microbial Life: Summarizing Milestone. . .
223
rod-shaped bacteria. And, although early in their development it was the bacteroid
structures which contained those things which looked like small bacteria, eventually
the bacteroids developed into something which contained no resemblance to
bacteria.
Brunchorst believed that rather than actual bacteria being involved in the bacteroids, the bacteroids were natural formations and normal organs that play a role in
the plant’s substance balance. By my translation, I would quote Brunchorst as stating
“If one assumes such activity of the bacteroids, it cannot be astonishing that they
approach the real organisms [bacteria], in appearance and chemical behavior in such
a way that they have so far been confused with them, while their development and
their dissolution [of the bacteroids] at the end of the vegetation [plants life cycle], as
set out above, shows that they are structures of the plasma of the legumes themselves
whose similar physiological function leads indeed [to a] most morphological resemblance to bacteria. After all, it is a very interesting case that the plasma of higher
plant cells can take on such a microorganism-like shape.”
Brunchorst similarly thought there was no reason to regard the bacteroids as
being either fungal spores or fungal organs. By my translation, I would quote
Brunchorst as stating “On the other hand, it is undoubted that, as Frank [presumably
Albert Bernhard Frank] says, they [the bacteroids] are actually surrounded by a
membrane” and that “This alone would make it unlikely that you would have
mushroom galls in front of you in the nodules”. Brunchorst further believed that
his findings, again by my translation “... force us to assume that we have it in the
nodules to be normal organs of the legumes, the bacteroids have to do with equally
normal organs of the cell plasma. It must always be noted what is beyond all doubt
that the nodules are only there for the bacteroids, only because of them [the
bacteroids, do the nodules] have a right to exist.”
Thusly, although Brunchorst used the word ‘symbiose’ in reference to the root
nodules, and Brunchorst is credited for establishing a hypothesis that a symbiosis
takes place through and in the nodules, he believed it was a symbiosis between the
legume and a fungus and that this symbiosis had nothing to do with the bacteroids.
Brunchorst believed that the nodules were organs which gave legumes an ability to
utilize any nitrogen-containing organic matter in the soil. Brunchorst developed his
opinion after studying Lupinus luteus, Trifolium pratense, Vicia sativa, and a few
other legume species. The plant group previously known as Leguminosae we now
consider to be Fabaceae. Microbiologists have since kept the term bacteroid. We also
have come to know that root nodule cells contain symbiosomes which enclose the
bacteria.
14 Discovering the Symbiotic Nature of Microbial Life: Summarizing Milestone. . .
223