In a brand new examine, researchers at the Indian Institute of Science (IISc) have unravelled the mystery behind how the lac insect produces laccaic acid that’s used to make lac pigment. The lac pigment is a prized commodity utilized in meals colouring, textiles, dyes, handicrafts, and people artwork.
According to IISc, the lac insect grows on sure timber (like the flame of the forest), drinks its sugary sap, and secretes a sticky resin referred to as shellac.
It additionally makes a brilliant purple compound referred to as laccaic acid, which is used to make the pigment. “How the insect produces laccaic acid has remained a source of mystery. For decades, scientists have unsuccessfully hunted for genes coding for its synthesis in the insect’s genome,” IISc mentioned.
However, now the researchers have discovered that the vibrant pigment extracted from the lac insect may very well be produced by a symbiotic yeast-like organism residing inside the insect.
The crew additionally confirmed that the yeast-like organism completely harbours genes coding for key elements in the pigment synthesis pathway.
India, a key producer
“For thousands of years, India has been a key producer of lac pigment. The pathway for the pigment production was not very clear,” mentioned Shantanu Shukla, assistant professor in the Department of Developmental Biology and Genetics, IISc.
IISc mentioned that one in all the key elements required for laccaic acid synthesis is an amino acid referred to as tyrosine, which the insect can’t make by itself or supply from the tree sap. Such lacking elements are normally provided by symbiotic micro organism or fungi that stay inside insect our bodies and secrete these molecules in alternate for housing.
The crew sequenced the total bacterial and fungal microbiome of the insect and zeroed in on two attainable candidates: a bacterium belonging to the Wolbachia genus and a yeast-like fungus. Previous research by different researchers had hinted at the presence of the fungus however had not recognized it or sequenced its genome.
In the present examine, the crew discovered that neither the insect nor the bacterium carried the genes wanted to make tyrosine and different elements of the pigment pathway. But the yeast-like organism did — it carried the total set of genes wanted for laccaic acid manufacturing. This contains genes coding for varied enzymes which catalyse the manufacturing of fragrant molecules which might be the constructing blocks of laccaic acid.
Inside egg cell
Mr. Shukla mentioned that the fungus is definitely inside the insect’s oocyte (egg cell). The fungus floats round in the insect’s haemolymph — the equal of animal blood — and as quickly as the oocyte matures, it latches on to it and enters the oocyte, and will get transmitted to the offspring that emerges from the oocyte.
Published – June 18, 2025 12:02 am IST
