Sandbox Reserved 1644: Difference between revisions

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== Structural highlights ==

From hLon main three domains, the ATPase domain and the C-terminal active site are those which confer to the protein its function.

The [https://en.wikipedia.org/wiki/ATPase ATPase] domain enables after the '''consumption of an ATP molecule''' to get the required energy for the active site to [https://en.wikipedia.org/wiki/Hydrolysis hydrolyze] protein substrates. It has been demonstrated that the presence of ADP induces a conformational change to obtain an '''asymmetric hexametric ring'''. As a result, the catalytic site reaches its '''open state''' where the protein substrate can bind. ATP most likely replaces ADP from the ATPase domain to cut off the next substrate. In presence of AMP the hexametric ring takes a '''closed conformation''' state suggesting that until either ATP or ADP is present in the environment, hLon has the capacity to perform its catalytic activity<ref>PMID: 27632940</ref>.

== Evolutionary conservation ==

The Lon proteolytic domain has a highly '''conserved structure'''. Like its orthologues, namely the eubacterium ''[https://fr.wikipedia.org/wiki/Escherichia_coli E. coli]'' ([https://proteopedia.org/wiki/index.php/1rre 1rre]), and the two archaea ''[https://en.wikipedia.org/wiki/Methanocaldococcus_jannaschii M. jannaschii]'' and ''[https://fr.wikipedia.org/wiki/Archaeoglobus_fulgidus A. fulgidus]'', it presents at its C-terminal a '''Ser-Lys dyad''' responsible of the substrate degradation activity. Although ''h''LonP active site resembles mostly to the one of ''Ec''LonP, the b5-sheet is replaced by an '''extension to a2'''. Thus, the N-terminal region of this helix carries the catalytic serine is a [https://en.wikipedia.org/wiki/310_helix 3(10) helix] and not a b-strand. As a consequence, ''h''LonP has the ability to bring the Asp852 into the active site to '''close''' it by forming a hydrogen bond with Lys898, a property already observed in ''Mj''Lon active site. This inactive state likely makes the catalytic serine inaccessible to the substrate and constraints the pKa of the lysine. Other main structural differences are '''loop shifts''' connecting the secondary structure elements b1 and b2, and a1<ref>PMID: 20222013</ref>.

The Lon proteolytic domain has a highly '''conserved structure'''. Like its orthologues, namely the eubacterium ''[https://fr.wikipedia.org/wiki/Escherichia_coli E. coli]'' ([https://proteopedia.org/wiki/index.php/1rre 1rre]), and the two archaea ''[https://en.wikipedia.org/wiki/Methanocaldococcus_jannaschii M. jannaschii]'' and ''[https://fr.wikipedia.org/wiki/Archaeoglobus_fulgidus A. fulgidus]'', it presents at its C-terminal a '''Ser-Lys dyad''' responsible of the substrate degradation activity. Although ''h''LonP active site resembles mostly to the one of ''Ec''LonP, the b5-sheet is replaced by an '''extension to a2'''. Thus, the N-terminal region of this helix carries the catalytic serine is a [https://en.wikipedia.org/wiki/310_helix 3(10) helix] and not a b-strand. As a consequence, ''h''LonP has the ability to bring the Asp852 into the active site to '''close''' it by forming a hydrogen bond with Lys898, a property already observed in ''Mj''Lon active site. This inactive state likely makes the catalytic serine inaccessible to the substrate and constraints the pKa of the lysine. Other main structural differences are '''loop shifts''' connecting the secondary structure elements b1 and b2, and a1 <ref>PMID: 20222013</ref>.

Sandbox Reserved 1644: Difference between revisions

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@@ Line 63: / Line 63: @@
 == Structural highlights ==
+From hLon main three domains, the ATPase domain and the C-terminal active site are those which confer to the protein its function.
+The [https://en.wikipedia.org/wiki/ATPase ATPase] domain enables after the '''consumption of an ATP molecule''' to get the required energy for the active site to [https://en.wikipedia.org/wiki/Hydrolysis hydrolyze] protein substrates. It has been demonstrated that the presence of ADP induces a conformational change to obtain an '''asymmetric hexametric ring'''. As a result, the catalytic site reaches its '''open state''' where the protein substrate can bind. ATP most likely replaces ADP from the ATPase domain to cut off the next substrate. In presence of AMP the hexametric ring takes a '''closed conformation''' state suggesting that until either ATP or ADP is present in the environment, hLon has the capacity to perform its catalytic activity<ref>PMID: 27632940</ref>.
 == Evolutionary conservation ==
-The Lon proteolytic domain has a highly '''conserved structure'''. Like its orthologues, namely the eubacterium ''[https://fr.wikipedia.org/wiki/Escherichia_coli E. coli]'' ([https://proteopedia.org/wiki/index.php/1rre 1rre]), and the two archaea ''[https://en.wikipedia.org/wiki/Methanocaldococcus_jannaschii M. jannaschii]'' and ''[https://fr.wikipedia.org/wiki/Archaeoglobus_fulgidus A. fulgidus]'', it presents at its C-terminal a '''Ser-Lys dyad''' responsible of the substrate degradation activity. Although ''h''LonP active site resembles mostly to the one of ''Ec''LonP, the b5-sheet is replaced by an '''extension to a2'''. Thus, the N-terminal region of this helix carries the catalytic serine is a [https://en.wikipedia.org/wiki/310_helix 3(10) helix] and not a b-strand. As a consequence, ''h''LonP has the ability to bring the Asp852 into the active site to '''close''' it by forming a hydrogen bond with Lys898, a property already observed in ''Mj''Lon active site. This inactive state likely makes the catalytic serine inaccessible to the substrate and constraints the pKa of the lysine. Other main structural differences are '''loop shifts''' connecting the secondary structure elements b1 and b2, and a1<ref>PMID: 20222013</ref>.
+The Lon proteolytic domain has a highly '''conserved structure'''. Like its orthologues, namely the eubacterium ''[https://fr.wikipedia.org/wiki/Escherichia_coli E. coli]'' ([https://proteopedia.org/wiki/index.php/1rre 1rre]), and the two archaea ''[https://en.wikipedia.org/wiki/Methanocaldococcus_jannaschii M. jannaschii]'' and ''[https://fr.wikipedia.org/wiki/Archaeoglobus_fulgidus A. fulgidus]'', it presents at its C-terminal a '''Ser-Lys dyad''' responsible of the substrate degradation activity. Although ''h''LonP active site resembles mostly to the one of ''Ec''LonP, the b5-sheet is replaced by an '''extension to a2'''. Thus, the N-terminal region of this helix carries the catalytic serine is a [https://en.wikipedia.org/wiki/310_helix 3(10) helix] and not a b-strand. As a consequence, ''h''LonP has the ability to bring the Asp852 into the active site to '''close''' it by forming a hydrogen bond with Lys898, a property already observed in ''Mj''Lon active site. This inactive state likely makes the catalytic serine inaccessible to the substrate and constraints the pKa of the lysine. Other main structural differences are '''loop shifts''' connecting the secondary structure elements b1 and b2, and a1 <ref>PMID: 20222013</ref>.