... the ITC method to the fully oxygenated dodecameric haemocyanin of the lobster Homarus vulgaris , cooperativity in binding has been found for the urate analogue caffeine but not for urate itself: using urate and the urate analogue caffeine as ligands, two conformations of the oxygenated pigment were...

...+ ]. It is concluded that in crustacean muscle caffeine and micromolar [Ca 2+ ] can release Ca 2+ from a ryanodine-sensitive store, which in many respects is similar to the sarcoplasmic reticulum of vertebrate skeletal and cardiac muscle. crab lobster muscle Carcinus maenas Homarus vulgaris caffeine Ca...

...A. Nies; B. Zeis; C. R. Bridges; M. K. Grieshaber ABSTRACT The haemocyanin of Homarus vulgaris possesses specific binding sites for L-lactate and urate, two allosteric modulators of haemocyanin oxygen-affinity. The affinities for both ligands have been determined. The dissociation constants, K D...

...B. Zeis; A. Nies; C. R. Bridges; M. K. Grieshaber ABSTRACT The specific effects of L-lactate and urate on oxygen binding by the haemo-cyanin of the lobster Homarus vulgaris were investigated. Increasing concentrations of L-lactate were found to increase haemocyanin oxygen-affinity. The relationship...