amino-acid starvation

Examples of amino-acid starvation in the following topics:

• The Stringent Response

  • The stringent response is a stress response that occurs in bacteria in reaction to amino-acid starvation or other stress conditions.
  • The stringent response, also called stringent control, is a stress response that occurs in bacteria and plant chloroplasts in reaction to amino-acid starvation , fatty acid limitation, iron limitation, heat shock, and other stress conditions.
  • This in turn causes the cell to divert resources away from growth and division and toward amino acid synthesis in order to promote survival until nutrient conditions improve.
  • The generic structure of an alpha amino acid in its un-ionized form.

• Activation of Starvation by Survival Genes

  • Stringent Response, also called stringent control, is a stress response that occurs in bacteria and plant chloroplasts in reaction to amino-acid starvation, fatty acid limitation, iron limitation, heat shock, and other stress conditions.
  • This in turn causes the cell to divert resources away from growth and division and toward amino acid synthesis in order to promote survival until nutrient conditions improve.

• The Incorporation of Nonstandard Amino Acids

  • Aside from the 22 standard amino acids, there are many other amino acids that are called non-proteinogenic or non-standard.
  • Also, most nascent polypeptides start with the amino acid methionine because the "start" codon on mRNA also codes for this amino acid.
  • Aside from the 22 standard amino acids, there are many other amino acids that are called non-proteinogenic or non-standard .
  • Some nonstandard amino acids are not found in proteins.
  • Nonstandard amino acids often occur as intermediates in the metabolic pathways for standard amino acids.

• Starvation-Induced Fruiting Bodies

  • Starvation-induced fruiting bodies can aggregate up to 500 micrometres long and contain approximately 100,000 bacterial cells.
  • When starved of amino acids, myxobacteria, or slime bacteria, detect surrounding cells in a process known as quorum sensing.

• Amino Acid Synthesis

  • These polymers are linear and unbranched, with each amino acid within the chain attached to two neighboring amino acids.
  • Twenty-two amino acids are naturally incorporated into polypeptides and are called proteinogenic or natural amino acids.
  • Amino acid synthesis depends on the formation of the appropriate alpha-keto acid, which is then transaminated to form an amino acid.
  • Aside from the 22 standard amino acids, there are many other amino acids that are called non-proteinogenic or non-standard.
  • Nonstandard amino acids often occur as intermediates in the metabolic pathways for standard amino acids — for example, ornithine and citrulline occur in the urea cycle, part of amino acid catabolism.

• Vitamins and Amino Acids

  • Microorganisms and plants can synthesize many uncommon amino acids and vitamins.
  • Amino acids are biologically important organic compounds made from amine (-NH2) and carboxylic acid (-COOH) functional groups, along with a side-chain specific to each amino acid.
  • The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen.
  • About 500 amino acids are known which can be classified in many ways.
  • Microorganisms and plants can synthesize many uncommon amino acids.

• Pyruvic Acid and Metabolism

  • Pyruvic acid (CH3COCOOH) is an organic acid, a ketone, and the simplest of the alpha-keto acids.
  • Pyruvic acid (CH3COCOOH; is an organic acid, a ketone, and the simplest of the alpha-keto acids.
  • It can also be used to construct the amino acid alanine, and it can be converted into ethanol.
  • Pyruvate can be converted into carbohydrates via gluconeogenesis, to fatty acids or energy through acetyl-CoA, to the amino acid alanine, and to ethanol.
  • It can also be used to construct the amino acid alanine and be converted into ethanol.

• Peptidoglycan Synthesis and Cell Division

  • Peptidoglycan, also known as murein, is a polymer and consists of sugars and amino acids which form the cell walls of bacteria.
  • Peptidoglycan, also known as murein, is a polymer consisting of sugars and amino acids that forms a mesh-like layer outside the plasma membrane of bacteria (but not Archaea; []), forming the cell wall.
  • Attached to the N-acetylmuramic acid is a peptide chain of three to five amino acids.
  • The peptidoglycan layer in the bacterial cell wall is a crystal lattice structure formed from linear chains of two alternating amino sugars, namely N-acetylglucosamine (GlcNAc or NAG) and N-acetylmuramic acid (MurNAc or NAM).
  • Cross-linking between amino acids in different linear amino sugar chains occurs with the help of the enzyme transpeptidase and results in a 3-dimensional structure that is strong and rigid.

• Primary and Secondary Metabolites

  • Primary and secondary metabolites are often used in industrial microbiology for the production of food, amino acids, and antibiotics.
  • These metabolites can be used in industrial microbiology to obtain amino acids, develop vaccines and antibiotics, and isolate chemicals necessary for organic synthesis.
  • Examples of primary metabolites include alcohols such as ethanol, lactic acid, and certain amino acids.
  • Additionally, primary metabolites such as amino acids-- including L-glutamate and L-lysine, which are commonly used as supplements-- are isolated via the mass production of a specific bacterial species, Corynebacteria glutamicum.
  • Describe how primary and secondary metabolites can be used in industrial microbiology to obtain amino acids, develop vaccines and antibiotics, and isolate chemicals for organic synthesis

• Unresolved Questions About the Origins of Life

  • For example, nucleic and amino acids can be made in laboratory simulations of the early earth, but how these acids polymerized to make the long chain needed for life is unknown.
  • The thermodynamic equilibrium of amino acid versus peptides is in the direction of separate amino acids.
  • The random association of single amino acids into one short protein string of 100 amino acids without some enzymatic help could take an incredible amount of time, longer than the age of the earth.
  • Polyphosphates cause polymerization of amino acids into peptides.
  • Such an atmosphere would diminish both the amount and variety of amino acids that could be produced.