Inactive proteinases in silkmoth moulting gel

Benita S Katzenellenbogen, Fotis C. Kafatos

Research output: Contribution to journalArticle

Abstract

The moulting gel of silkmoths lacks proteolytic activity but contains an inactive form of the proteinases which are later found in the moulting fluid. These inactive enzymes are activatable in vitro by dilution, activation proceeding most rapidly at low ionic strength. Activation proceeds as a first-order process and is not autocatalytic. Approximately the full amount of proteinases ultimately found in moulting fluid are already present in the gel. Moulting gel does not inhibit the active proteinases of moulting fluid; moreover, the proteolytic activity elicited by dilution of the moulting gel does not disappear upon reconcentration. These observations suggest that the proteinases in moulting gel are not inhibited by a stable, dissociable inhibitor; they may be present either as compartmentalized active enzymes or as proenzymes. Several possible mechanisms for the in vivo activation at the time of gel to fluid transformation are discussed.

Original languageEnglish (US)
Pages (from-to)823-832
Number of pages10
JournalJournal of insect physiology
Volume17
Issue number5
DOIs
StatePublished - May 1971
Externally publishedYes

Fingerprint

Molting
Bombyx
molting
Peptide Hydrolases
proteinases
Gels
gels
zymogens
Enzyme Precursors
Enzymes
ionic strength
enzymes
Osmolar Concentration
fluids

ASJC Scopus subject areas

  • Physiology
  • Insect Science

Cite this

Inactive proteinases in silkmoth moulting gel. / Katzenellenbogen, Benita S; Kafatos, Fotis C.

In: Journal of insect physiology, Vol. 17, No. 5, 05.1971, p. 823-832.

Research output: Contribution to journalArticle

Katzenellenbogen, Benita S ; Kafatos, Fotis C. / Inactive proteinases in silkmoth moulting gel. In: Journal of insect physiology. 1971 ; Vol. 17, No. 5. pp. 823-832.
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