734 



AbStraCt.-A 66 kDa glycoprotein 

 selected from SDS-PAGE gel profiles of 

 soluble extracts of Lutjanus griseus was 

 purified by Fast Protein Liquid Chro- 

 matography technology. A polyclonal 

 antiserum produced to the single- 

 chained glycoprotein was tested with 14 

 other lutjanid extracts in Western blots 

 and produced 3 different patterns: 

 strong reactions with L. jocu and L. 

 apodus; weak reactions with L. buc- 

 canella, L. synagris, L. analis, L. 

 campechanus, Pristipomoid.es aqui- 

 lonaris, Ocyurus chrysurus, and Apsilus 

 dentatus; no reactions with L. vivanus, 

 L. mahogoni, L. cyanopterus, Etelis 

 oculata, and the hybrid L. synagris x O. 

 chrysurus. The anti-66 kDa antiserum 

 also reacted strongly with soluble ex- 

 tracts of oocytes and juveniles of L. 

 griseus. Adsorption of the IgG fraction 

 of the antiserum with glutaraldehyde- 

 insolubilized L. apodus extract resulted 

 in an antiserum that remained strongly 

 reactive with L. griseus extract but that 

 was weakly reactive with L. apodus 

 extract and negative with L. jocu ex- 

 tract in Western blots. The N-terminal 

 amino acid sequence analyses of the 

 first 10 residues of the purified 66 kDa 

 proteins of L. griseus and L. jocu were 

 approximately the same, but only 3 of 

 10 residues were the same with the 

 purified proteins of L. griseus and L. 

 apodus. Extracts of L. apodus con- 

 tained 3 additional proteins that were 

 not detected in extracts of L. griseus 

 as determined by SDS-PAGE. This evi- 

 dence for both interspecies and species- 

 specific protein determinants is cur- 

 rently being used to produce species- 

 specific polyclonal and monoclonal an- 

 tisera for identifying species of lutjanid 

 fishes at early life history stages. 



Immunologic methods for species 



identification of early life stages of 



lutjanid fishes from the western 



central Atlantic. 



Part I: Characterization 



of an interspecies protein 



Duane R. Schultz 

 Patricia I. Arnold 



Department of Medicine, University of Miami School of Medicine 



Miami. Florida 3310! 



e-mail address: dianeschu@aol com 



Thomas R. Capo 

 Claire B. Paris-Limouzy 

 Joseph E. Serafy 



The Rosenstiel School of Marine and Atmospheric Science 

 University of Miami, Miami, Florida 33 I 49 



William J. Richards 



Southeast Fisheries Science Center 

 National Marine Fisheries Service, NOAA 

 Miami, Florida 33149 



Manuscript accepted 19 June 1996 

 Fishery Bulletin 94:734-742 (19 



Eighteen species of snappers (Lut- 

 janidae I, representing 5 genera, are 

 found in the western Atlantic Ocean 

 (Robins et al., 1991). Species iden- 

 tification of the early life stages of 

 snappers is incomplete because 

 meristic characters are very simi- 

 lar or equivocal within the family. 

 In addition, identification of mor- 

 phological features requires a 

 great deal of time and experience. 

 Innovative studies are necessary for 

 further species-specific identifica- 

 tion of early life stages (eggs, lar- 

 vae, and early juveniles) because in- 

 formation is available for only a few 

 species and each exhibits a complex 

 recruitment strategy (Richards et 

 al., 1994). Lutjanids constitute one 

 of the major predators of coral-graz- 

 ing species, but the detrimental im- 



pact of overfishing and habitat loss 

 from pollution and development is 

 rapidly leading to an imbalance in 

 the fragile equilibrium of the reef 

 community. Thus, the ability to 

 identify the early life stages of spe- 

 cific lutjanids is an important as- 

 pect of conservation measures. 



Specific antibodies directed against 

 a minor protein may be useful for 

 species identification at the early 

 life stages (Diano et al., 1992). In 

 our study, starting with the devel- 

 opment of biochemical methods to 

 isolate a very pure antigen, we have 

 produced a polyclonal antibody for 

 prototypic studies of previously dif- 

 ficult or unapproachable questions 

 of identification of early life history 

 specimens of snapper. These meth- 

 ods and immunologic reagents have 



