Primary structure of two major cuticular proteins from the migratory locust, Locusta migratoria, and their identification in polyacrylamide gels by mass spectrometry
C. Jensen et al., Primary structure of two major cuticular proteins from the migratory locust, Locusta migratoria, and their identification in polyacrylamide gels by mass spectrometry, BBA-PROT ST, 1429(1), 1998, pp. 151-162
Citations number
28
Categorie Soggetti
Biochemistry & Biophysics
Journal title
BIOCHIMICA ET BIOPHYSICA ACTA-PROTEIN STRUCTURE AND MOLECULAR ENZYMOLOGY
The complete amino acid sequence has been determined for two proteins, LmAC
P21 and LmACP22, which are prominent components of adult pharate cuticle fr
om the migratory locust, Locusta migratoria. The proteins have relative mol
ecular masses (M-r) of 16853 and 16879, respectively. They were purified by
standard chromatographic methods, and the primary structures were determin
ed by combined use of mass spectrometry and automatic Edman degradation. Th
e proteins are characterized by the presence of a conserved, hydrophilic ce
ntral sequence with pronounced similarity to sequences reported for cuticul
ar proteins from other insect species, while the N- and C-terminal regions
are dominated by the amino acids alanine, valine and proline. The electroph
oretic identity of the two proteins was confirmed by matrix assisted laser
desorption ionization mass spectrometry (MALDIMS) of the electroeluted LmAC
P21/22 proteins from a two-dimensional electrophoresis gel. The mass spectr
ometric analysis established the presence of additional proteins in close p
roximity to the LmACP21/22 gel spot. One of these proteins, M-r 16134, was
identified as LmACP18, and enzymatic digestion indicated that it is structu
rally closely related to LmACP21 and LmACP22. (C) 1998 Elsevier Science B.V
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