A series of steps or a cycle of reactions that could achieve the enrichment of phosphatidylinositol with 1-stearoyl-2-archidonoyl phosphatidylinositol needs to be proposed. Concept Introduction: The phosphatidylinositol cycle involves in cell signaling. Its major purpose is to synthesize phosphatidylinositol and its phosphorylated forms. The lipid intermediate of PI cycle are highly enriched with 1-stearoyl-2-arachidnoyl molecular species. This enrichment is retained as long as the intermediates are segregated from other lipids. What happens in the enrichment of a particular phospholipid molecule is selective addition of one specific type of alkyl or the acyl chain. There are several enzymes that involve in the conversion of phospholipids to exhibit specific acyl or alkyl chains.

Question

Some of the following four amino acids : alanine, arginine, histidine, aspartic acid would provide a side chain for acid-base catalysis at physiological pH (assume pK of each amino acid is equal to pK value for the free amino acid in solution). Explain for each amino acid how and why each would or would not provide the side chain residue to support acid-base catalysis at physiological pH.

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Question

Chapter 24, Problem 20P

Interpretation Introduction

Interpretation:

A series of steps or a cycle of reactions that could achieve the enrichment of phosphatidylinositol with 1-stearoyl-2-archidonoyl phosphatidylinositol needs to be proposed.

Concept Introduction:

The phosphatidylinositol cycle involves in cell signaling. Its major purpose is to synthesize phosphatidylinositol and its phosphorylated forms. The lipid intermediate of PI cycle are highly enriched with 1-stearoyl-2-arachidnoyl molecular species. This enrichment is retained as long as the intermediates are segregated from other lipids. What happens in the enrichment of a particular phospholipid molecule is selective addition of one specific type of alkyl or the acyl chain. There are several enzymes that involve in the conversion of phospholipids to exhibit specific acyl or alkyl chains.

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