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Updated: Jul 25, 2026
08:55
Facile Protocol for the Synthesis of Self-assembling Polyamine-based Peptide Amphiphiles (PPAs) and Related Biomaterials
Published on: June 25, 2018
Summary
Polyamines like spermine, spermidine, and putrescine are vital molecules in all organisms. Their precise molecular functions, despite influencing protein synthesis and cell functions, remain largely unknown.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- Polyamines (spermine, spermidine, putrescine) are ubiquitous in living organisms.
- They are synthesized from amino acids and transported across cell membranes.
- Polyamines are also degraded into various compounds with poorly understood roles.
Purpose of the Study:
- To explore the known functions of polyamines.
- To highlight the gaps in understanding their molecular mechanisms of action.
Main Methods:
- Literature review of polyamine synthesis, degradation, and known functions.
- Analysis of polyamine roles in transcriptional and translational processes.
- Examination of polyamine involvement in membrane stabilization and neurophysiology.
Main Results:
- Polyamines significantly influence protein synthesis at transcriptional and translational levels.
- They play a role in stabilizing cellular membranes.
- In mammals, polyamines modulate neurophysiological functions and may act as intracellular messengers.
Conclusions:
- Polyamines are essential biomolecules with diverse cellular roles.
- Despite their known influences, the molecular mechanisms underlying polyamine action are largely unelucidated.
Related Concept Videos
01:21Basicity of Aliphatic Amines
Amines can behave as Brønsted–Lowry bases by accepting a proton from the acid to form corresponding conjugate acids. Due to a lone pair of nonbonding electrons, aliphatic amines can also act as Lewis bases by forming a covalent bond with an electrophile.
To measure the basicity of amines, two conventions are generally used. The first defines Kb as the basicity constant for the deprotonation reaction of water by the amine, as presented in Figure 1. Conventionally, lower Kb indicates higher...
To measure the basicity of amines, two conventions are generally used. The first defines Kb as the basicity constant for the deprotonation reaction of water by the amine, as presented in Figure 1. Conventionally, lower Kb indicates higher...
01:25Basicity of Heterocyclic Aromatic Amines
Heterocyclic amines, where the N atom is a part of an alicyclic system, are similar in basicity to alkylamines. Interestingly, the heterocyclic amine having a nitrogen atom as part of an aromatic ring has much less basicity than its corresponding alicyclic counterpart. For this reason, as presented in Figure 1, piperidine (pKb = 2.8) is significantly more basic than pyridine (pKb = 8.8).
01:30Preparation of Amines: Alkylation of Ammonia and Amines
Alkylation is one of the methods used to prepare amines. Direct alkylation of ammonia or a primary amine with an alkyl halide gives polyalkylated amines along with a quaternary ammonium salt through successive SN2 reactions. This process of making the quaternary salt through the direct alkylation method is called exhaustive alkylation.
Each alkylation step makes the nitrogen center more nucleophilic, which triggers successive alkylations until a quaternary ammonium salt is formed. Considering...
Each alkylation step makes the nitrogen center more nucleophilic, which triggers successive alkylations until a quaternary ammonium salt is formed. Considering...
01:07Amines: Introduction
Amines are organic derivatives of ammonia. They are formed by replacing one or more ammonia protons with alkyl or aryl groups. Depending upon the number of organyl groups bonded to nitrogen, amines are classified as primary, secondary, or tertiary. Primary amines have one organyl group attached to the nitrogen atom, while secondary and tertiary amines have two and three organyl groups attached to the nitrogen atom, respectively.
01:26Physical Properties of Amines
Amines with low molecular weight are usually gaseous at room temperature, while those with high molecular weight are liquid or solids in nature. Usually, low molecular weight amines have a rotten fish-like smell. Diamines typically have a pungent smell. For instance, cadaverine and putrescine, depicted in Figure 1, are two molecules responsible for decaying tissue.
01:18Basicity of Aromatic Amines
The basicity of aromatic amines is much weaker than that of aliphatic amines due to the involvement of the lone pair of electrons over the N atom in resonance with the aryl rings. Generally, the electron-donating ability of any substituents on the aryl ring of aromatic amines increases the basicity of the amine by increasing electron density, and hence the availability of lone pair on the nitrogen. On the other hand, electron-withdrawing functional groups on the aryl ring of amines decrease the...