eQuant - A Server for Fast Protein Model Quality Assessment by Integrating High-Dimensional Data and Machine Learning

  • Sebastian Bittrich
  • Florian Heinke
  • Dirk Labudde
Conference paper
Part of the Communications in Computer and Information Science book series (CCIS, volume 613)


In molecular biology, reliable protein structure models are essential in order to understand the functional role of proteins as well as diseases related to them. Structures are derived by complex and resource-demanding experiments, whereas in silico structure modeling and refinement approaches are established to cope with experimental limitations. Nevertheless, both experimental and computational methods are prone to errors. In consequence, small local regions or even the whole tertiary structure can be unreliable or erroneous, leading the researcher to formulate false hypotheses and draw false conclusions.

Here, we present eQuant, a novel and fast model quality assessment program (MQAP) and server. By utilizing a hybrid approach of established MQAPs in combination with machine learning techniques, eQuant achieves more homogeneous assessments with less uncertainty compared to other established MQAPs. For normal sized protein structures, computation requires less than ten seconds, making eQuant one of the fastest MQAPs available. The eQuant server is freely available at


Protein structure Structure quality Quality assessment Quality scoring eQuant 



The authors thank the Free State of Saxony and the Saxon Ministry of Science and the Fine Arts for funding.

Conflict of Interest. The authors declare that there are no conflicts of interest.


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  • Sebastian Bittrich
    • 1
  • Florian Heinke
    • 1
  • Dirk Labudde
    • 1
  1. 1.University of Applied Science MittweidaMittweidaGermany

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