Mar 1, 1976

Quenching of tryptophanyl fluorescence of human growth hormone by iodide

Chemico-biological Interactions
V T Maddaiah, P J Collipp


Quenching of tryptophanyl fluorescence of human growth hormone by I- followed saturation kinetics and was abolished by KSCN. In the presence of 6 M guanidine hydrochloride quenching was linear between 0 to 0.2 M KI. These results suggest that I- quenched the fluorescence of the native hormone by binding at or near the single tryptophanyl residue. Quenching by 0.1 M KI decreased exponentially with increasing concentrations of human and bovine growth hormones. Acidification did not have a significant effect on quenching of the human hormone, but it markedly decreased quenching of the bovine hormone. Conformational differences at the vicinity of the lone tryptophanyl residue that could be inferred by these and other experiments may be contributing to the biological specificity of native human and bovine growth hormones.

  • References5
  • Citations1


  • References5
  • Citations1


Mentioned in this Paper

Bos taurus
Acidification - ActCode
Fluorescence Spectroscopy
Plasma Protein Binding Capacity
Protein Conformation
Potassium thiocyanate
Guanidine Hydrochloride
Growth hormone, bovine
Recombinant Growth Hormone

About this Paper

Trending Feeds


Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Bone Marrow Neoplasms

Bone Marrow Neoplasms are cancers that occur in the bone marrow. Discover the latest research on Bone Marrow Neoplasms here.

IGA Glomerulonephritis

IgA glomerulonephritis is a chronic form of glomerulonephritis characterized by deposits of predominantly Iimmunoglobin A in the mesangial area. Discover the latest research on IgA glomerulonephritis here.

Cryogenic Electron Microscopy

Cryogenic electron microscopy (Cryo-EM) allows the determination of biological macromolecules and their assemblies at a near-atomic resolution. Here is the latest research.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

LRRK2 & Immunity During Infection

Mutations in the LRRK2 gene are a risk-factor for developing Parkinson’s disease. However, LRRK2 has been shown to function as a central regulator of vesicular trafficking, infection, immunity, and inflammation. Here is the latest research on the role of this kinase on immunity during infection.

Antiphospholipid Syndrome

Antiphospholipid syndrome or antiphospholipid antibody syndrome (APS or APLS), is an autoimmune, hypercoagulable state caused by the presence of antibodies directed against phospholipids.

Meningococcal Myelitis

Meningococcal myelitis is characterized by inflammation and myelin damage to the meninges and spinal cord. Discover the latest research on meningococcal myelitis here.

Alzheimer's Disease: MS4A

Variants within membrane-spanning 4-domains subfamily A (MS4A) gene cluster have recently been implicated in Alzheimer's disease by recent genome-wide association studies. Here is the latest research.