Current Microbiology

, Volume 70, Issue 2, pp 228–234 | Cite as

Potential Mode of Protection of Silkworm Pupae from Environmental Stress by Harboring the Bacterial Biofilm on the Surfaces of Silk Cocoons

  • Pranab K. Halder
  • Deboki Naskar
  • Akash Kumar
  • Juming Yao
  • Subhas C. Kundu
  • Anindya S. GhoshEmail author


The silkworm forms cocoon to protect its pupa that survives for months inside the cocoon without being affected by various environmental stresses. To understand the possible mode of pupal survival within the cocoon encasement, we investigate the cause that protects the cocoon. During the end of the spinning process, we have isolated different bacterial species from the cocoon surface. These are identified using molecular techniques and checked for their abilities to form biofilm in vitro. The bacteria are able to form biofilm either individually or in consortia. Of which, Bacillus and Erwinia species are prominent biofilm formers. Interestingly, these bacteria have the ability to form biofilm on the cocoon mimetic surface of the silk protein Sericin Hope that contains only sericin. The origin and the behavior of the bacteria lead us to hypothesize the possible role of biofilm layer on the cocoon surface, which provides protection from adverse environmental conditions.


Bacterial Isolate Extracellular Polymeric Substance Stromatolite Calcium Oxalate Microbacterium 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The work was supported in parts by three different grants. One from Department of Biotechnology (DBT) to SCK and two from Department of Biotechnology and North East (DBT-NE) Twinning grant and Council of Scientific and Industrial Research (CSIR) from Govt. of India to ASG.

Conflict of interest

The authors declare no commercial or financial conflict of interest.


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Pranab K. Halder
    • 1
  • Deboki Naskar
    • 1
  • Akash Kumar
    • 1
  • Juming Yao
    • 2
  • Subhas C. Kundu
    • 1
  • Anindya S. Ghosh
    • 1
    Email author
  1. 1.Department of BiotechnologyIndian Institute of Technology KharagpurKharagpurIndia
  2. 2.College of Materials and TextilesZhejiang Sci-Tech UniversityHangzhouPeople’s Republic of China

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