Letter | Published:

Keratin Digestion in the Larvæ of the Clothes Moth

Naturevolume 135pages10391040 (1935) | Download Citation



THE digestion of keratin in the larvæ of the ordinary clothes moth, Tineola biselliella, was investigated by means of the micro-methods developed by Linderstrøm-Lang and Holter. In the secretion of the middle intestine a powerful proteinase was found having a pH optimum about 9.3 (40°, splitting up casein) and, contrary to animal trypsin-kinase, being but little sensitive to addition of thiol compounds (sodium sulphide, sodium thioglycolate). The pH of the secretion of animals fed with wool was about 10 (measured with the glass electrode in a carbon dioxide free chamber) and gave a strong nitro-prusside reaction which was most clearly visible in the half-digested hairs present as contamination in the secretion. The reaction disappeared soon after the secretion had been exposed to the air; only a very small further visible change of the hairs was observable when the secretion (with half-digested hairs) was kept in a moist chamber after removal from the intestine. Animals fed with cotton wool or filter-paper (made inviting to the animal by covering it with a thin film of casein and wool-fat) gave scarcely any nitroprusside reaction, but the reaction reappeared when cystin was added to this food (although this is left quite undigested by the animal).

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.


  1. 1

    W. T. Astbury, Trans. Faraday Soc., 29, 103; 1933.

  2. 2

    J. B. Speakman and Hirst M.C., Trans. Faraday Soc., 29, 148; 1933.

  3. 3

    D. R. Goddard and L. Michaelis, J. Biol. Chem., 106, 605; 1934.

  4. 4

    E. Titschack, Z. tech. Biol., 10, 92; 1922.

Download references

Author information


  1. Carlsberg Laboratorium, Kobenhavn

    •  & F. DUSPIVA


  1. Search for K. LINDERSTRØM-LANG in:

  2. Search for F. DUSPIVA in:

About this article

Publication history

Issue Date



Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.