Words similar to carbonyl
Example sentences for: carbonyl
How can you use “carbonyl” in a sentence? Here are some example sentences to help you improve your vocabulary:
Lhcb6, a minor LHCP, contains Gly instead of Pro at the position analogous to 82 in Lhcb1, thus eliminating the peptide bond carbonyl of Gly as a ligand, but Lhcb6 has a potential ligand for Chl b in Gln83 [ 39 40 ] . These two LHCP sub-species, along with Lhca4 are most affected by the lack of Chl b in vivo [ 5 ] . Lhcb4 (apoprotein of CP29) has Val instead of Pro at 'position 82', and the absence of site a 6 in Lhcb4 may contribute to its drastic reduction in Chl b -less mutants [ 5 8 ] . However, Lhcb2, Lhcb3, Lhca1, Lhca2 and Lhca3 contain the Gly peptide carbonyl as a ligand (each has Pro at 'position 82' [ 40 ] ) but are reduced only slightly, if any, in amount by the lack of Chl b.
For example, steric hindrance caused by substitution of bulky Phe for Gly78 (residue numbers are given with reference to Lhcbl) in the position designated a 6 [ 29 ] prevented this peptide carbonyl, non-H-bonded because of Pro82 one helical turn further, from serving as a ligand (see Fig.
3) It displays an amide group that occupies a cavity not filled by nicotine or acetylcholine, and makes a network of hydrogen bonds with the indole nitrogen of alpha4-Trp182, the backbone carbonyl of beta2-Ser133 and beta2-Phe144, and with the backbone nitrogen of beta2-Leu146 (Figure 5B).
predicted that Phe158 and Ile 164 form hydrophobic interactions with bulky substituents on the substrate, suggesting that the loss of these residues would only affect binding of substrates with large aromatic substituents [ 37 ] . In the modeling studies on CcrA [ 42 ] , Asn233 was predicted to interact with the β-lactam carbonyl on substrate, and mutagenesis studies have supported this prediction [ 43 ] . Although Asn233 is sequence conserved in L1 [ 35 ] , it is located 14Å away from the modeled position of the β-lactam carbonyl and was predicted not to play a role in substrate binding to L1 [ 37 ] . On the other hand, the substrate-binding model predicted that Tyr228 was in position to offer a hydrogen bond to the β-lactam carbonyl and participate in an oxyanion hole that was proposed to form as the substrate was hydrolyzed [ 37 ] . By using the crystal structure and modeling studies on L1, Ullah et al.
The substrate-binding model showed that Tyr228 in L1 was position-conserved with Asn233 in the other crystallographically characterized metallo-β-lactamases [ 37 42 44 45 46 ] . Spencer and coworkers postulated that Tyr228 is part of an oxyanion hole that interacts with the β-lactam carbonyl on substrate and helps to stabilize the putative tetrahedral intermediate formed during substrate turnover [ 37 ] . To test this hypothesis, Tyr228 was changed to an alanine and to a phenylalanine to afford the Y228A and Y228F mutants, respectively.
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