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. 1980 Jul;77(7):4040–4043. doi: 10.1073/pnas.77.7.4040

Stopped-flow x-ray scattering: the dissociation of aspartate transcarbamylase.

M F Moody, P Vachette, A M Foote, A Tardieu, M H Koch, J Bordas
PMCID: PMC349764  PMID: 6933451

Abstract

A combination of stopped-flow and x-ray scattering techniques was used to study the dissociation of aspartate transcarbamylase (carbamoylphosphate:L-aspartate carbamoyltransferase, EC 2.1.3.2) with a 2:1 excess of p-chloromercuribenzenesulfonic acid (the ratio being calculated on a basis of reactive sites), in the presence and absence of the transition state analogue N-(phosphonacetyl)-L-aspartate. At 10 mg of protein per ml, the scattering curves allowed some details of the reaction to be followed with a time resolution down to 1 sec. The curves showed not only the dissociation of the enzyme complex but also the formation of the subunits. These results show that, with present facilities, x-ray scattering could be used to study dissociation or reassociation reactions with a time resolution of the order of 100 msec.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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