Changes Log

The entries in the log are arranged in chronological order, with the most recent changes at the top. If you wish to search for changes to a particular enzyme, then enter ec:x.y.z.w (repacing x.y.z.w by the relevant EC number) in the search text box at the top of the page. Other terms can be entered in the text box to limit the results obtained.

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ID	Date/Time	EC/Citation Key	Table	Field	Changed From	Changed To
287835	2024-02-24 18:02:49	5.6.2.7	entry	serial		7
287834	2024-02-24 18:02:49	5.6.2.7	entry	subsubclass		2
287833	2024-02-24 18:02:49	5.6.2.7	entry	subclass		6
287832	2024-02-24 18:02:49	5.6.2.7	entry	class		5
287831	2024-02-24 18:02:49	5.6.2.7	entry	links		BRENDA, EXPASY, IUBMB, KEGG
287830	2024-02-24 18:02:49	5.6.2.7	entry	comments		RNA helicases, which participate in nearly all aspects of RNA metabolism, utilize the energy from ATP hydrolysis to unwind RNA. The engine core of helicases is usually made of a pair of RecA-like domains that form an NTP binding cleft at their interface. Changes in the chemical state of the NTP binding cleft (binding of the NTP or its hydrolysis products) alter the relative positions of the RecA-like domains and nucleic acid-binding domains, creating structural motions that disrupt the pairing of the nucleic acid, causing separation and unwinding. While most RNA helicases utilize a mechanism known as canonical duplex unwinding and translocate along the RNA (cf. EC 5.6.2.5, RNA 5\'-3\' helicase and EC 5.6.2.6, RNA 3\'-5\' helicase), DEAD-box RNA helicases differ by unwinding RNA via the local strand separation mechanism, which does not involve translocation. These helicases load directly on the duplex region, aided by single stranded or structured nucleic acid regions. Upon loading, the DEAD-box protein locally opens the duplex strands. This step requires binding of ATP, which is not hydrolysed. The local helix opening causes the remaining basepairs to dissociate without further action from the enzyme. Unwinding occurs without apparent polarity, and is limited to relatively short distances. ATP hydrolysis is required for release of the DEAD-box protein from the RNA. The name originates from the sequence D-E-A-D, which is found in Motif II of these proteins.
287829	2024-02-24 18:02:49	5.6.2.7	entry	sys_name		RNA helicase (non-translocating)
287828	2024-02-24 18:02:49	5.6.2.7	entry	other_names		Dbp2; DDX3; DDX4; DDX5; DDX17; DDX3Y; RM62; hDEAD1; RNA helicase Hera; DED1
287827	2024-02-24 18:02:49	5.6.2.7	entry	reaction		ATP + H2O + wound RNA = ADP + phosphate + unwound RNA
287826	2024-02-24 18:02:49	5.6.2.7	entry	accepted_name		DEAD-box RNA helicase
287825	2024-02-24 18:02:49	5.6.2.7	entry	ec_num		5.6.2.7
287729	2024-02-24 18:02:48	5.6.2.6	entry	serial		6
287728	2024-02-24 18:02:48	5.6.2.6	entry	subsubclass		2
287727	2024-02-24 18:02:48	5.6.2.6	entry	subclass		6
287726	2024-02-24 18:02:48	5.6.2.6	entry	class		5
287725	2024-02-24 18:02:48	5.6.2.6	entry	links		BRENDA, EXPASY, IUBMB, KEGG
287724	2024-02-24 18:02:48	5.6.2.6	entry	comments		RNA helicases, which participate in nearly all aspects of RNA metabolism, utilize the energy from ATP hydrolysis to unwind RNA. The engine core of helicases is usually made of a pair of RecA-like domains that form an NTP binding cleft at their interface. Changes in the chemical state of the NTP binding cleft (binding of the NTP or its hydrolysis products) alter the relative positions of the RecA-like domains and nucleic acid-binding domains, creating structural motions that disrupt the pairing of the nucleic acid, causing separation and unwinding. Most RNA helicases utilize a mechanism known as canonical duplex unwinding, in which the helicase binds to a single stranded region adjacent to the duplex and then translocates along the bound strand with defined directionality, displacing the complementary strand. Most of these helicases proceed 3\' to 5\' (type A polarity), but some proceed 5\' to 3\' (type B polarity - cf. EC 5.6.2.5, RNA 5\'-3\' helicase), and some are able to catalyse unwinding in either direction [1,3]. Most canonically operating helicases require substrates with single stranded regions in a defined orientation (polarity) with respect to the duplex. A different class of RNA helicases, EC 5.6.2.g, DEAD-box RNA helicase, use a different mechanism and unwind short stretches of RNA with no translocation.
287723	2024-02-24 18:02:48	5.6.2.6	entry	sys_name		RNA 3\'-5\' helicase (ATP-hydrolysing)
287722	2024-02-24 18:02:48	5.6.2.6	entry	other_names		DEAH/RHA protein; DEAH-box protein 2; Prp22p; DHX8; DHX36; CSFV NS3 helicase; nonstructural protein 3 helicase; KOKV helicase; Kokobera virus helicase; hepatitis C virus NS3 protein; DExH protein; MTR4; SKI2; BRR2; SUV3; Rig-I; retinoic-acid-inducible gene I; DbpA
287721	2024-02-24 18:02:48	5.6.2.6	entry	reaction		n ATP + n H2O + wound RNA = n ADP + n phosphate + unwound RNA
287720	2024-02-24 18:02:48	5.6.2.6	entry	accepted_name		RNA 3\'-5\' helicase
287719	2024-02-24 18:02:48	5.6.2.6	entry	ec_num		5.6.2.6