It is well-known that sharks have enamel which consists of the very hard mineral fluoroapatite. So far, no scientist has investigated this with high-end chemical and physical methods." This was now done by Epple and his colleague from the MPIE Professor Dierk Raabe, together with Dr Oleg Prymak and Joachim Enax. The main part of the work was carried out at UDE. The MPIE was the institute, where especially the mechanical measurements took place.
For this study the teeth of shortfin mako shark and tiger shark were literally "taken apart" – for these shark species have different habits of eating their prey. By scanning electron microscopy and X-ray diffraction, the scientists analyzed the order, the size and the nature of the fluoroapatite crystals and determined the hardness of the teeth locally in small areas with mechanical measurements.
Epple and his co-workers showed that the chemical and crystallographic composition of teeth is similar in different shark species, although mako sharks "tear" into the flesh of their prey while tiger sharks "cut" it. The interior consists of the more elastic dentin; the outer part is the highly mineralized enamel.
Thus one might suppose that shark teeth are harder than human teeth. "The human enamel consists of a little softer mineral, hydroxyapatite, which is incidentally also present in bones." By carrying out a comparative study with a human tooth, the scientists discovered something surprisingly new: It is just as robust as that of that fearful animal. "This is due to the special micro- and nanostructure of our teeth.The crystals in human teeth have a special arrangement and they are "glued together" by proteins, which stops cracks from running through the whole tooth", said Epple, who is also a member of the Center for Nanointegration Duisburg-Essen (CENIDE). Incidentally nature has equipped all creatures similarly: If teeth were fully mineralized they would be in danger of cracking upon mechanical shock.
The research findings are published in the recent issue of the Journal of Structural Biology, 178 (2012). DOI http://dx.doi.org/10.1016/j.jsb.2012.03.012.Further information: Prof. Dr. Matthias Epple, University of Duisburg-Essen, +49 0201/183-2413, email@example.com
Ulrike Bohnsack | idw
Unravelling the genetics of fungal fratricide
16.10.2018 | Uppsala University
Fungal weapon turns against the maker
16.10.2018 | Leibniz-Institut für Naturstoff-Forschung und Infektionsbiologie - Hans-Knöll-Institut (HKI)
Augsburg chemists present a new technology for compressing, storing and transporting highly volatile gases in porous frameworks/New prospects for gas-powered vehicles
Storage of highly volatile gases has always been a major technological challenge, not least for use in the automotive sector, for, for example, methane or...
When we put water in a freezer, water molecules crystallize and form ice. This change from one phase of matter to another is called a phase transition. While this transition, and countless others that occur in nature, typically takes place at the same fixed conditions, such as the freezing point, one can ask how it can be influenced in a controlled way.
We are all familiar with such control of the freezing transition, as it is an essential ingredient in the art of making a sorbet or a slushy. To make a cold...
Thin organic layers provide machines and equipment with new functions. They enable, for example, tiny energy recuperators. In future, these will be installed...
Das Zusammenspiel aus Struktur und Dynamik bestimmt die Funktion von Proteinen, den molekularen Werkzeugen der Zelle. Durch Fortschritte in der...
New measurement method allows researchers to precisely follow the movement of individual molecules over long periods of time
The function of proteins – the molecular tools of the cell – is governed by the interplay of their structure and dynamics. Advances in electron microscopy have...
16.10.2018 | Event News
02.10.2018 | Event News
01.10.2018 | Event News
16.10.2018 | Life Sciences
16.10.2018 | Physics and Astronomy
16.10.2018 | Event News