A Modified Markov Clustering Approach for Protein Sequence Clustering

  • Lehel Medvés
  • László Szilágyi
  • Sándor M. Szilágyi
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5265)


In this paper we propose a modified Markov clustering algorithm for efficient clustering of large protein sequence databases, based on previously evaluated sequence similarity criteria. The proposed alteration consists in an exponentially decreasing inflation rate, which aims at helping the quick creation of the hard structure of clusters by using a strong inflation in the beginning, and at producing fine partitions with a weaker inflation thereafter. The algorithm, which was tested and validated using the whole SCOP95 database, or randomly selected 10-50% sections, generally converges within 12-14 iteration cycles and provides clusters of high quality. Furthermore, a novel generalized formula is given for the inflation operation, and an efficient matrix symmetrization technique is presented, in order to improve the partition quality with relatively low amount of extra computations. A large graph layout technique is also employed for the efficient visualization of the obtained clusters.


Markov clustering protein sequence clustering sparse matrix large graph layout SCOP95 database 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Lehel Medvés
    • 1
  • László Szilágyi
    • 1
    • 2
  • Sándor M. Szilágyi
    • 1
  1. 1.Sapientia - Hungarian Science University of TransylvaniaFaculty of Technical and Human ScienceTârgu-MureşRomania
  2. 2.Department of Control Engineering and Information TechnologyBudapest University of Technology and EconomicsBudapestHungary

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