2129 



Ghiretti, F.,and A. Ghiretti-Magaldi . 1972. 



Respiratory proteins in mollusks. In Chemical Zoology. VII. Mollusca. 

 Marcel Florkin and Bradley T. Scheer (eds.). Academic Press, New York: 

 201-217. 



Muscle myoglobin of Mercenaria mercenaria has a very high oxygen affinity 

 (T u = 0.55 mm Hg) , the hemocoelic hemoglobins, either dissolved or contained 

 in the erythrocytes, show considerably lower oxygen affinity (Manwell 1963). 

 - J.L.M. 



2130 



Gilles, R. 1970. 



Intermediary metabolism and energy production in some invertebrates. 

 Arch. Internatl. Physiol. Biochim. 78: 313-326. 



Adductor muscle of Mercenaria mercenaria (Tappel 1960) contains the following 

 concentrations of respiratory chain components: a = 0.08, a 3 = 0.8, b = 5.3, 

 c + ci = 3.7, and fp = 3.8 yM/kg wet weight. - J.L.M. 



2131 



Gilles, R. 1972. 



Biochemical ecology of mollusca. In Chemical Zoology. VII. Mollusca. 

 Marcel Florkin and Bradley T. Scheer (eds.). Academic Press, Nev; York: 

 467-499. 



Table II is from Gilles (1970) and shows, among other species, the concen- 

 tration of the respiratory chain components in muscle of Mercenaria 

 mercenaria. The respiratory chain component concentration in uM/kg wet 

 weight was: a = 0.08, a 3 = 0.8, b = 5.3, c + Cj = 3.7, and fp = 3,8 in 

 adductor muscle. - J.L.M. 



2132 



Gordon, J. 1980. 



Evidence for sclerotization of the shell matrix of a marine bivalve. 

 Proc. Natl. Shellf. Assn. 70: 125-126 (abstract). 



Scanning electron micrographs of sections of shell of Mercenaria mercenaria 

 show prominent growth lines, especially in the prismatic region of the 

 shell. The lines seem to become indistinct near the growing shell margin. 

 When shell is decalcified and thin sections of insoluble shell matrix are 

 treated histochemically , lysine, tyrosine, and a phenoloxidase can be 

 identified in regions of the section corresponding to most recent growth of 

 shell. It is suggested that progressive polymerization of the matrix takes 

 place after shell deposition, the entire process taking 2 to 3 days to be 

 complete. Cross-linking of organic molecules is effected by amino-quinone 

 bonds involving epsilon-amino groups and tyrosine. The ultrastructural 

 appearance of growth lines near the edge of calcified sections can be ex- 

 plained by differential solubility of regions of organic matrix exposed to 

 preparatory treatments. - modified author's abstract - J.L.M. 



2133 



Gordon, J., and M. R. Carriker. 1980. 



Sclerotized protein in the shell matrix of a bivalve mollusc. Mar. 

 Biology 57(4): 251-260. 



The epsilon-amino groups of lysine and phenolic groups of tyrosine are most 

 heavily concentrated in newly deposited organic matrix of shell of Mercenaria 

 mercena.rio.. A phenoloxidase enzyme which oxidizes L-dihydroxyphenylalanine 

 is present only in this "new" area of shell matrix. Scanning electron micro- 

 graphs of calcified secretions of shell show that accretion lines, thought to 

 be layers of organic matrix separating diurnal accretions of calcium carbon- 

 ate, are not developed until up to 4 days after deposition of shell material. 



593 



