Question

In nature, certain metabolic processes are carried out by microbes that team up to get the job done, a cozy arrangement called a consortium. Such is the case with the oxidation of methane (CH4) linked to the reduction of sulfate ( S 2 in anoxic marine sediments. The overall reaction C 4 + SO2 근 HCO3 HS + H2O s exergonic and the s mall amount o energy released is shared between wo distinct microbes. The methane oxidizer the consortium is a species of Archaea nicknamed ANME (for anacrobic methanotroph, blue in photo), and its sulfate-reducing partner is a species of Bactena (brown in photo). The consortium is thought to play a key role in the carbon cycle as a major methane sink, and thus a detailed picture of how it works is important to our understanding of the global carbon economy, climate change, and marine biogeochemistry. Researchers have tried for years to separate the consortium into its components but always found that methane oxidation required both organisms. However, some researchers hypothesized that it might be poesible to replace the sulfate reducer with an artificial electron acceptor and that this might unlock the consortium and allow the methanotroph to grow in pure culture. Using an electron acceptor called AODS, the scientists discovered that they could turn off sulfate reduction in the consortium while maintaining CH4 oxidation. During this process, the methanotroph used electrons from CH4 to reduce AQDS rather than passing them on to its sulfate-reducing partner. Several other electron acceptors known to support anaerobic respiration also sustained methane oxidation, giving hope that ANME may eventually be obtained in pure culture The ability to grow a microbe in pure culture is the "gold standard" for the study of its physiology, biochemistry, regulation, and several other aspects of its biology. In the case of the ANME-sulfate reducer consortium, several physiologies were active at once, and resolving these many reactions proved to be a major scientific challenge. However, if further work shows that ANME can be removed from the consortium and grown in pure culture, detailed aspects of its biology can be studied that were not possible when the organism was tightly coupled to its partner in the consortium (photo).

Answer 1

1. Answer:-
(a) PURE CULTURE NEEDED:-
-Regulation of metabolism in ANME
-Metabolic requirements of ANME
-Rate of sulfate reduction

(b) PURE CULTURE NOT NEEDED:-
-Process of methane oxidation
-Generation time in nature

2. Answer:-
(a) Complex medium:- a medium containing digests such as beef extract
(b) Defined medium :- a medium containing carefully measured amount of different chemicals so that the exact amount that of composition is known.
(c) Enriched medium :- a medium with blood added to support the growth of fastidious microbes.
(d) Differential medium:- a salt rich medium that allows only halophiles.
(e) Selective medium:- a medium that changes colour if a fermentative organism is present but stays the same colour if non fermentative organism is present.