From Wikipedia, the free encyclopedia
Organism that thrives in an oxygenated environment
An
aerobic organism
or
aerobe
is an
organism
that can survive and grow in an
oxygenated
environment.
[1]
The ability to exhibit aerobic respiration may yield benefits to the aerobic organism, as aerobic respiration yields more energy than anaerobic respiration.
[2]
Energy production of the cell involves the synthesis of
ATP
by an enzyme called
ATP synthase
. In aerobic respiration, ATP synthase is coupled with an electron transport chain in which oxygen acts as a terminal electron acceptor.
[3]
In July 2020,
marine biologists
reported that aerobic
microorganisms
(mainly), in "
quasi-suspended animation
", were found in
organically poor sediments
, up to 101.5 million years old, 250 feet below the
seafloor
in the
South Pacific Gyre
(SPG) ("the deadest spot in the ocean"), and could be the
longest-living life forms
ever found.
[4]
[5]
Types
[
edit
]
When an organism is able to survive in both oxygen and anaerobic environments, the use of the
Pasteur effect
can distinguish between facultative anaerobes and aerotolerant organisms. If the organism is using fermentation in an anaerobic environment, the addition of oxygen will cause facultative anaerobes to suspend fermentation and begin using oxygen for respiration. Aerotolerant organisms must continue fermentation in the presence of oxygen.
Facultative organisms grow in both oxygen rich media and oxygen free media.
Aerobic Respiration
[
edit
]
Aerobic organisms use a process called
aerobic respiration
to create ATP from ADP and a phosphate.
Glucose
(a
monosaccharide
) is oxidized to power the electron transport chain:
[8]
This equation is a summary of what happens in three series of biochemical reactions:
glycolysis
, the
Krebs cycle
(also known as the
Citric acid cycle
), and
oxidative phosphorylation
.
- C
6
H
12
O
6
+ 6 O
2
+ 38
ADP
+ 38 phosphate → 6 CO
2
+ 44 H
2
O + 38
ATP
In Oxidative phosphorylation, ATP is synthesized from ADP and a phosphate using ATP synthase. ATP synthase is powered by a proton-motive force created by using the energy generated from the electron transport chain. A
hydrogen ion
(H
+
) has a positive charge and if separated by a cellular membrane, it creates a difference in charge between the inside and outside of the membrane. Oxidative phosphorylation occurs in the
mitochondria
of
eukaryotes
.
[3]
Aerobic respiration needs O
2
because it acts as the terminal electron acceptor in prokaryotes' electron transport chain. Molecular Oxygen is reduced to water in this process.
[9]
See also
[
edit
]
References
[
edit
]
- ^
"aerobe"
at
Dorland's Medical Dictionary
- ^
Kroneck PM, Sosa Torres ME, eds. (2021).
Metals, Microbes, and Minerals - The Biogeochemical Side of Life
(1st ed.). Berlin: de Gruyter GmbH & Co. KG.
ISBN
978-3-11-058890-3
.
OCLC
1201187551
.
- ^
a
b
Morelli AM, Ravera S, Panfoli I (October 2020).
"The aerobic mitochondrial ATP synthesis from a comprehensive point of view"
.
Open Biology
.
10
(10): 200224.
doi
:
10.1098/rsob.200224
.
PMC
7653358
.
PMID
33081639
.
- ^
Wu KJ (28 July 2020).
"These Microbes May Have Survived 100 Million Years Beneath the Seafloor - Rescued from their cold, cramped and nutrient-poor homes, the bacteria awoke in the lab and grew"
.
The New York Times
. Retrieved
31 July
2020
.
- ^
Morono Y, Ito M, Hoshino T, Terada T, Hori T, Ikehara M, et al. (July 2020).
"Aerobic microbial life persists in oxic marine sediment as old as 101.5 million years"
.
Nature Communications
.
11
(1): 3626.
Bibcode
:
2020NatCo..11.3626M
.
doi
:
10.1038/s41467-020-17330-1
.
PMC
7387439
.
PMID
32724059
.
- ^
a
b
c
Todar K. "Nutrition and Growth of Bacteria".
Todar's Online Textbook of Bacteriology
. p. 4
. Retrieved
24 July
2016
.
- ^
Hentges DJ (1996). "17: Anaerobes:General Characteristics". In Baron S (ed.).
Medical Microbiology
(4 ed.). Galveston, Texas: University of Texas Medical Branch at Galveston.
ISBN
9780963117212
.
PMID
21413255
. Retrieved
24 July
2016
.
- ^
Chauhan BS (2008).
Principles of Biochemistry and Biophysics
. Laxmi Publications. p. 530.
ISBN
978-8131803226
.
- ^
Borisov, Vitaliy B.; Verkhovsky, Michael I. (23 October 2015). Stewart, Valley (ed.).
"Oxygen as Acceptor"
.
EcoSal Plus
.
6
(2): ecosalplus.ESP?0012?2015.
doi
:
10.1128/ecosalplus.ESP-0012-2015
.
ISSN
2324-6200
.
PMID
26734697
.