Chapter 8
Miraculous Fixation of Molecular Nitrogen
from the Atmosphere
Vladimír Klaban
Abstract The fact that microorganisms are able to collect molecular nitrogen from
the atmosphere and convert that into a more biologically usable form is a key factor
in the production of plant life and that nitrogen eventually gets incorporated into
proteins up through the food chain. This is one miraculous example of the way in
which microorganisms serve as the foundation of our biosphere. This essay summarizes the involved biological processes and the history of our related discoveries.
8.1 Introduction
In the past, these bacteria used to be called “nitrogenic bacteria.” The term nitrogenic
is derived from words “Nitrogenium” for nitrogen and “gennao” meaning creation.
That would suggest nitrogenic bacteria could “create or synthesize nitrogen” which,
logically, is not true. Diazotrophic bacteria form a part of nitrogen circulation in
nature, more specifically of the so-called biochemical nitrogen cycle. Let’s begin our
examination of nitrogen fixation from the atmosphere from a viewpoint of
bioenergy. Such fixation is essential for soil fertility and therefore plant production.
8.2 Fixation of Nitrogen from the Bioenergy Point of View
Gaseous nitrogen is diatomic, meaning that it is a two-atom molecule. That form of
nitrogen has the two atoms held together by a triple bond. For that reason, N 2
represents a very stable molecule, and splitting it requires a considerable amount
of energy (946 kJ/mol). It is this splitting of a strong bond which is a condition for
nitrogen fixation. The overall reaction can be expressed by this simple equation:
V. Klaban (*)
Sobčice, Czech Republic
© Springer Nature Switzerland AG 2021
C. J. Hurst (ed.), Microbes: The Foundation Stone of the Biosphere, Advances in
Environmental Microbiology 8, https://doi.org/10.1007/978-3-030-63512-1_8
143
Miraculous Fixation of Molecular Nitrogen
from the Atmosphere
Vladimír Klaban
Abstract The fact that microorganisms are able to collect molecular nitrogen from
the atmosphere and convert that into a more biologically usable form is a key factor
in the production of plant life and that nitrogen eventually gets incorporated into
proteins up through the food chain. This is one miraculous example of the way in
which microorganisms serve as the foundation of our biosphere. This essay summarizes the involved biological processes and the history of our related discoveries.
8.1 Introduction
In the past, these bacteria used to be called “nitrogenic bacteria.” The term nitrogenic
is derived from words “Nitrogenium” for nitrogen and “gennao” meaning creation.
That would suggest nitrogenic bacteria could “create or synthesize nitrogen” which,
logically, is not true. Diazotrophic bacteria form a part of nitrogen circulation in
nature, more specifically of the so-called biochemical nitrogen cycle. Let’s begin our
examination of nitrogen fixation from the atmosphere from a viewpoint of
bioenergy. Such fixation is essential for soil fertility and therefore plant production.
8.2 Fixation of Nitrogen from the Bioenergy Point of View
Gaseous nitrogen is diatomic, meaning that it is a two-atom molecule. That form of
nitrogen has the two atoms held together by a triple bond. For that reason, N 2
represents a very stable molecule, and splitting it requires a considerable amount
of energy (946 kJ/mol). It is this splitting of a strong bond which is a condition for
nitrogen fixation. The overall reaction can be expressed by this simple equation:
V. Klaban (*)
Sobčice, Czech Republic
© Springer Nature Switzerland AG 2021
C. J. Hurst (ed.), Microbes: The Foundation Stone of the Biosphere, Advances in
Environmental Microbiology 8, https://doi.org/10.1007/978-3-030-63512-1_8
143