A structural and functional evaluation of the allosteric response of aspartate transcarbamoylase from Erwinia herbicola /

activated by ATP and inhibited by CTP; its CTP inhibition is

Bibliographic Details
Main Author:	Glaser, Shannon Stroud
Format:	Thesis eBook
Language:	English
Published:	[Place of publication not identified] : [publisher not identified] ; 1994.
Subjects:	Major biochemistry.
Online Access:	Link to OAKTrust copy

Description
Summary:	activated by ATP and inhibited by CTP; its CTP inhibition is aspartate transcarbamoylases (EC 2.1.3.2, ATCase) which are assembled in vivo using the catalytic and regulatory subunits coli holoenzyme. The hybrid holoenzyme assembled in vivo CTP, and no effect by CTP in the presence of UTP. These CTP, and synergistic inhibition by CTP in the presence of CTP. E. coli and Proteus vulgatis. The regulatory dimers tended exhibited activation by ATP, inhibition by CTP, and from E. herbicola and regulatory subunits from E. coli from E. herbicola exhibited no response to ATP, inhibition by from E. herbicola with catalytic and regulatory subunits from heterologous effects are consistent with the allosteric heterotropic regulation are present among the divergent holoenzyme from Erwinia herbicola is not affected by ATP and holoenzyme from Proteus vulgafis is activated by ATP and CTP, hybrid enzymes. Holoenzymes formed with regulatory dimers hybrid holoenzyme assembled in vivo with catalytic subunits hybrid holoenzyme lacked synergistic inhibition of CTP in the inhibited by CTP in the presence of UTP. The ATCase observations mimick the allosteric response of the native E. only slightly inhibited by CTP, yet it is synergistically presence of UTP while UTP did counteract the activation of response of the native P. vulgaiis holoenzyme. However, this species. The ATCase holoenzyme from Escheiichia coli is structurally similar, unique differences in homotropic and subunits from P. vulgaris exhibited activation by ATP and synergistic inhibition to CTP in the presence of UTP. These synergistically enhanced in the presence of UTP. The ATCase than that found for the native E. herbicola enzyme. The to dictate the nature of the allosteric response in mixed UTP. CTP inhibition was greater in the hybrid holoenzymes UTP. In this study, hybrid enzymes have been heterologously with catalytic subunits from E. herbicola and regulatory yet it is synergistically inhibited by CTP in the presence of
Item Description:	"Major subject: Biochemistry". Vita.
Physical Description:	xiii, 104 leaves : illustrations ; 28 cm. Also available online.
Bibliography:	Includes bibliographical references.