Mutations that remove the 2’-OH of the A residue at the 30 end of the P-site tRNA result in a 106-fold reduction in catalysis rates. This “substrate-assisted catalysis”

2’-OH of the P-site tRNA may act as part of a “proton shuttle”

TLS Online TPP Program

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#Unit 13. Methods in Biology

A more attractive alternative is to cover the reaction mixture with a plug of inert wax and place the critical reagent on top of this plug. 

TLS Online TPP Program

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#Unit 3. Fundamental Processes

Rho is a member of the family of hexameric ATP-dependent helicases. Each subunit has an RNA-binding domain and an ATP hydrolysis domain.

TLS Online TPP Program

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#Unit 4. Cell Communication and Cell Signaling

Third mechanism for maintaining tolerance, in addition to T-cell anergy and apoptosis, is through the activity of regulatory T cells (TREG cells).

TLS Online TPP Program

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#Unit 3. Fundamental Processes

TLS Online TPP Program

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#Unit 3. Fundamental Processes

The ter site is recognized by a unidirectional contrahelicase (called Tus in E. coli and RTP in B. subtilis) that recognizes the consensus sequence and prevents the replication fork from proceeding.