0
Research Papers

Reversibility of Functional and Structural Changes of Lysozyme Subjected to Hydrodynamic Flow

[+] Author and Article Information
Burcu Kaplan Türköz1

Biological Sciences and Engineering Program, Faculty of Natural Sciences and Engineering,  Sabanci University, Tuzla, Istanbul, Turkey 34956

Anastassia Zakhariouta

Biological Sciences and Engineering Program, Faculty of Natural Sciences and Engineering,  Sabanci University, Tuzla, Istanbul, Turkey 34956

Muhsincan Sesen

Mechatronics Program, Faculty of Natural Sciences and Engineering,  Sabanci University, Tuzla, Istanbul, Turkey, 34956

Alpay Taralp2

Materials Science and Engineering Program,Faculty of Natural Sciences and Engineering,  Sabanci University, Tuzla, Istanbul, Turkey, 34956taralp@sabanciuniv.edu

Ali Koşar2

Mechatronics Program, Faculty of Natural Sciences and Engineering,  Sabanci University, Tuzla, Istanbul, Turkey, 34956kosara@sabanciuniv.edu

1

Present adress: Université Lyon 1, Univ Lyon, France; CNRS, UMR 5086; Bases Moléculaires et Structurales des Systèmes Infectieux, IBCP 7 passage du vercors, F-69367, France.

2

Corresponding authors.

J. Nanotechnol. Eng. Med. 3(1), 011006 (Aug 14, 2012) (7 pages) doi:10.1115/1.4006363 History: Received April 07, 2011; Revised January 20, 2012; Published August 13, 2012; Online August 14, 2012

In this initial study, the effect of hydrodynamic flow on lysozyme structure and function was investigated using a microchannel device. Protein was subjected to bubbly cavitation as well as noncavitating flow conditions at pH 4.8 and 25 °C. Interestingly, time course analyses indicated that the secondary structure content, the hydrodynamic diameter, and enzymatic activity of lysozyme were unaffected by cavitation. However, noncavitating flow conditions did induce a decrease of the hydrodynamic diameter. The corresponding structural change was subtle to the extent that bioactivity was marginally suppressed. Moreover, native diameter and bioactivity could be fully restored following a brief period of ultrasonication. The findings encouraged further study of various hydrodynamic flow conditions in order to better ascertain the potential risks and benefits of invasive hydrodynamic cavitation in medicine. The results also served to highlight the counter-intuitive notion that proteins need not necessarily be denatured in high-shear media, risks that typically correlate well with forcefully agitated solutions.

FIGURES IN THIS ARTICLE
<>
Copyright © 2012 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

(a) Setup used to provide and control hydrodynamic flow and (b) microchannel configuration showing the orifice throat and exit

Grahic Jump Location
Figure 2

Twelve percentage of SDS-PAGE analysis of lysozyme subjected to hydrodynamic treatment at a Ci value of (a) 7.6. Lanes: (1) MW markers, arrow indicates 15 kDa band, (2) untreated control protein, (3)–(7) 25, 49, 172, 343, and 1200-fold flow-diluted sample protein, respectively, and (b) 0.93. Lanes: (1) MW markers, arrow indicates 15 kDa band, (2) control protein, (3)–(7) 25, 49, 172, 343, and 1200-fold flow-diluted sample protein, respectively. Protein samples, diluted over the course of the flow treatment, were withdrawn for analysis at the indicated dilution factors. In order to normalize the protein band intensities, the more concentrated samples were appropriately diluted with Buffer A (see Sec. 2) prior to adding SDS loading buffer. A 2.2 μg aliquot of protein sample was loaded into each well.

Grahic Jump Location
Figure 3

CD spectra of lysozyme subjected to hydrodynamic treatment at a Ci value of (a) 0.93 or (b) 7.6. Protein samples, diluted over the course of the flow treatment, were withdrawn for analysis at the indicated dilution factors.

Grahic Jump Location
Figure 4

Secondary structure content of lysozyme subjected to hydrodynamic treatment at a Ci value of (a) 0.93 or (b) 7.6. Protein samples, diluted over the course of the flow treatment, were withdrawn for analysis at the indicated dilution factors.

Grahic Jump Location
Figure 5

Average hydrodynamic diameter of lysozyme subjected to (a) hydrodynamic treatment at a Ci value of 0.93, (b) hydrodynamic treatment at a Ci value of 7.6 and (c) hydrodynamic treatment at a Ci value of 7.6 followed by 30s of ultrasonication. Protein samples, diluted over the course of the flow treatment, were withdrawn for analysis at the indicated dilution factors. Control samples, assessed at concentrations corresponding to each treated sample, were generated by a series of manual dilutions of untreated lysozyme.

Grahic Jump Location
Figure 6

Relative activity of lysozyme subjected to (a) hydrodynamic treatment at a Ci value of 0.93, (b) hydrodynamic treatment at a Ci value of 7.6 and (c) hydrodynamic treatment at a Ci value of 7.6 followed by 30s of ultrasonication. Protein samples, diluted over the course of the flow treatment, were withdrawn for analysis at the indicated dilution factors. Assays were carried out as described in Sec. 2.

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In