Hemocyanin of the Spider Eurypelma Californicum: Amino Acid Sequence of Subunit a and of the Smaller Cb-Peptides of Subunits b and c

Complete Sequence of the 24-mer Hemocyanin of the TarantulaEurypelma californicum

“…11 of 36 cDNAs were found to code for the known hemocyanin subunits a (24, 26), d (22), and e (23,26). Comparison with partial amino acid sequences of different hemocyanin subunits that had been determined before (37)(38)(39)(40)(41) allowed the unambiguous assignment of the residual open reading frames to subunit b, c, f, and g. Because all these cDNAs represented N-terminally truncated versions missing between 30 and 500 base pairs at the 5Ј end, the corresponding full-length cDNAs were obtained by a polymerase chain reaction-based approach. The sequences of the full-length cDNAs have been deposited in the EMBL/GenBank TM data base (Table I).…”

Tarantula hemocyanin mRNA

“…In spite of this we can be sure that all seven subunit types are coded by individual mRNAs and do not arise by posttranslational modifications. This had already been shown by the distinct peptide patterns and enzymatic cleavage, and is now being proven by five complete (d [32], e [31]) or partial (a [33], 6, c, W. Schartau, personal communication) amino acid sequences. Although the in vitro translation system used was not designed to detect minor posttranslational modifications, obviously the antigenic reactivity of the products did not differ significantly from the native hemocyanin subunits, if there are any minor modifications in vivo in the hemocytes.…”

“…Under these conditions authentic dissociated Eurypelma hemocyanin migrates as a series of five bands. Subunits d andf, c and g are usually not well separated in this system [33]. The virtual identity of the electrophoretic patterns of authentic Eurypelma hemocyanin and the immunoprecipitated translation products proves in vitro synthesis of hemocyanin in rabbit reticulocyte lysates.…”