According to Research, a Biomolecule Called Diphthamide Can Also Be Found in Plants

Diphthamide is a biomolecule that is required for the normal synthesis of proteins in cells.

When people become infected with diphtheria, the diphtheria toxin alters diphthamide, causing life-threatening problems due to decreased protein synthesis.

Diphthamide has previously only been found in animals and fungus. A study team has recently shown that the biomolecule exists in plants as well.

The Achilles heel of plants and animals

(Photo : Chris Abney/Unsplash)

Diphthamide is a natural alteration of the elongation factor-2 protein found in many species. This protein is one of the components responsible for the synthesis of all proteins in the cell, as per ScienceDaily.

According to Ute Krämer, this alteration has long been recognized to be the target of diphtheria toxin, which can induce life-threatening problems in patients infected with diphtheria by blocking cellular protein production.

Diphtheria illnesses produced by bacteria have been reported from ancient times and were widely feared until the 19th century when a vaccine was discovered.

Diphthamide had previously only been detected and thoroughly investigated in animal species and baker's yeast - as a model organism for medicinal study.

Ute Krämer's team has recently demonstrated that diphthamide is also created in plants and serves a vital function if a plant lacks the capacity to form diphthamide, there is an increased mistake rate in protein production.

Furthermore, plant growth is slowed as a result of decreased cell division. Several other changes in key cellular regulatory mechanisms might also contribute to the growth limitation.

According to the study's findings, the key first step in the manufacture of diphthamide known from mammals and yeast also occurs in plants.

As a result, it is likely that the succeeding stages leading up to the diphthamide presently identified in plants are the same.

According to the study's findings, the key first step in the manufacture of diphthamide known from mammals and yeast also occurs in plants.

As a result, it is likely that the succeeding stages leading up to the diphthamide presently identified in plants are the same.

What is novel, according to Ute Krämer, is that not only genetic abnormalities can cause diphthamide loss.

Environmental stress, particularly an excess of the nutritional trace element copper or the environmental toxin cadmium, suppresses the production of diphthamide in plants.

Human cells exhibited diphthamide insufficiency in the presence of high copper contents.

These findings suggest a new element controlling plant growth rates and may help to improve knowledge of how these diseases develop.

What is diphthamide?

Diphthamide is a posttranslational alteration produced from S-adenosyl methionine (SAM) that is only present on elongation factor 2 (EF2), as per Sciencedirect.

Diphthamide's structure was discovered decades ago. However, the multistep biosynthetic routes were just recently discovered.

Proteins implicated in the process are currently being studied.

Diphthamide is the target of various bacterial toxins, including diphtheria toxin and Pseudomonas exotoxin A, since it is a unique alteration that occurs exclusively on one protein in the cell.

However, in many cell lines, removing this mutation produces no discernible phenotypic. Diphthamide's precise physiological role is currently unclear.

The initial step in the biosynthesis of diphthamide was hypothesized to be the creation of a C-C bond between the histidine residue and the 3-amino-3-carboxypropyl group of S-adenosyl-L-methionine (SAM).