Energy, Ecology and Environment

, Volume 3, Issue 2, pp 110–125 | Cite as

Effect of vegetative filter strips on the dynamics of E. coli biofilm-building potential and expression of virulence factors at Mau, Kenya

  • Casianes Owino Olilo
  • Anastasia Wairimu Muia
  • Japheth Ogalo Onyando
  • Wilkister Nyaora Moturi
Original Article


Escherichia coli (E. coli) populations could become tolerant to extreme environmental temperatures to become resident in soil and surface water habitats creating public health problems. The objective of this study was to understand the interaction between dynamics of E. coli genetic diversity, physiology, and vegetative filter strips (VFS) in overland flows and soil habitats. Pulse-field gel electrophoresis was used to establish the genetic diversity of the isolates (n = 4). Genotypic analysis showed that the runoff isolates do not form a single genetic strain, but that multiple genotype strains were capable of surviving and proliferating in these habitats. High overall unique genotypic diversity was observed in VFS II (38.5%) as compared to VFS III (9.5%) and VFS I (1.5%). Approximately 8.5% E. coli genotypes observed in the surface water and 5.5% observed in soil habitat were shared between different sampling sites, suggesting diffuse sources of E. coli in these habitats. Approximately 32.5% genotypic overlap and a limited sharing (72.5%) between soil and surface water habitats were observed. These findings inferred that certain E. coli strains might have the ability to colonize and adapt to soil and runoff surface water habitats through production of biofilms. Thus, these results confirm that biofilm formation confers competitive advantage to the E. coli environmental isolates including hardiness, versatility, higher resistance to ecological and physical impacts and higher resource availability.


Vegetated filter strip design Genetic and physiological adaptations E. coli populations Overland flow Soil habitat Biofilm formation 



This study was designed by among others Eng. Professor Japheth O. Onyando, the chairperson, Department of Agricultural Engineering and Technology; Dr. Anastasia W. Muia, the Department of Biological Sciences; and Dr. Wilkister N. Moturi, Department of Environmental Science. Our deepest appreciation goes to the Dean Faculty of Agriculture for granting us the permission to work in field 18 of Tatton Agriculture Park (TAP). We appreciate The Nakuru County Laboratory for the use of their facility for microbial analyses. We wish to thank The Department of Water and Civil Engineering of Egerton University provided the Meteorological data from Egerton University weather station. The Director, Kenya Marine and Fisheries Research Institute (KMFRI), Prof James M. Njiru who granted me the study grant under Egerton University (EU)_KMFRI Memorandum of Understanding (MOU) Study Programme is highly appreciated. This study was funded by The Kenya National Commission of Science and Technology, the Science, Technology and Innovation Ph.D. research Grant, under Grant nos: NCST/ST and I/RCD/4th Call PhD/181.

Compliance with ethical standards

Conflict of interest

On behalf of all authors, the corresponding author states that there is no conflict of interest.


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Copyright information

© Joint Center on Global Change and Earth System Science of the University of Maryland and Beijing Normal University and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Casianes Owino Olilo
    • 3
  • Anastasia Wairimu Muia
    • 1
  • Japheth Ogalo Onyando
    • 2
  • Wilkister Nyaora Moturi
    • 3
  1. 1.Department of Biological SciencesEgerton UniversityEgertonKenya
  2. 2.Department of Agricultural Engineering and TechnologyEgerton UniversityEgertonKenya
  3. 3.Department of Environmental ScienceEgerton UniversityEgertonKenya

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