A Novel Catalytic Function of Synthetic IgG‐Binding Domain (Z Domain) from Staphylococcal Protein A: Light Emission with Coelenterazine

Abstract

The synthetic IgG-binding domain (Z domain) of staphylococcal protein A catalyzes the oxidation of coelenterazine to emit light like a coelenterazine-utilizing luciferase. The Z domain derivatives (ZZ-gCys, Z-gCys and Z-domain) were purified and the luminescence properties were characterized by comparing with coelenterazine-utilizing luciferases, including Renilla luciferase, Gaussia luciferase and the catalytic 19 kDa protein of Oplophorus luciferase. Three Z domain derivatives showed luminescence activity with coelenterazine and the order of the initial maximum intensity of luminescence was ZZ-gCys (100%) > Z-gCys (36.8%) > Z-domain (1.1%) > bovine serum albumin (BSA; 0.9%) > staphylococcal protein A (0.1%) and the background value of coelenterazine (0.1%) in our conditions. The luminescence properties of ZZ-gCys showed the similarity to that of Gaussia luciferase, including the luminescence pattern, the emission spectrum, the stimulation by halogen ions and nonionic detergents and the substrate specificity for coelenterazine analogues. In contrast, the luminescence properties of Z-gCys were close to the catalytic 19 kDa protein of Oplophorus luciferase. The catalytic region of the Z domain for the luminescence reaction might be different from the IgG-binding region of the Z domain.

ChemInform Abstract: Synthetic Routes to Coelenterazine and Other Imidazo[1,2‐a]pyrazin‐3‐one Luciferins: Essential Tools for Bioluminescence‐Based Investigations

“…[109] Unfortunately,atoxicity by necrosis was observed in am ore recent report when injecting high doses of h-coelenterazine (149) into mice. [40j] Moreover,i ns erum,ahigher degree of autoxidation of this type of luciferin, which can be causedb ya lbumin [110] or IgG-binding domain, [111] was observedi nc omparison with buffers used for in vitro studies. [112] This problem is sometime compensated by as tronger bioluminescent signal.…”

Synthetic Routes to Coelenterazine and Other Imidazo[1,2‐a]pyrazin‐3‐one Luciferins: Essential Tools for Bioluminescence‐Based Investigations

“…Unfortunately, a toxicity by necrosis was observed in a more recent report when injecting high doses of h‐ coelenterazine ( 149 ) into mice 40j. Moreover, in serum, a higher degree of autoxidation of this type of luciferin, which can be caused by albumin110 or IgG‐binding domain,111 was observed in comparison with buffers used for in vitro studies 112. This problem is sometime compensated by a stronger bioluminescent signal.…”

Luminescence of Cypridina Luciferin in the Presence of Human Plasma Alpha 1-Acid Glycoprotein

“…Supporting this hypothesis, previous papers have reported luminescence of Cypridina luciferin or its imidazopyrazinone-type analogs in the presence of molecules that have hydrophobic cavities responsible for their compound-binding abilities (e.g., cyclodextrins or serum albumins) [ 15 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ]. The mechanism of luminescence in the presence of a serum albumin or a cyclodextrin is not well understood, but it is suggested that the hydrophobic cavities of these molecules are involved [ 15 , 30 ].…”