Uric Acid Spherulites in the Reflector Layer of Firefly Light Organ

Goh, King-Siang; Sheu, Hwo-Shuenn; Hua, Tzu-En; Kang, Mei-Hua; Li, Chia-Wei
February 2013
PLoS ONE;Feb2013, Vol. 8 Issue 2, p1
Academic Journal
Background: In firefly light organs, reflector layer is a specialized tissue which is believed to play a key role for increasing the bioluminescence intensity through reflection. However, the nature of this unique tissue remains elusive. In this report, we investigated the role, fine structure and nature of the reflector layer in the light organ of adult Luciola cerata. Principal Findings: Our results indicated that the reflector layer is capable of reflecting bioluminescence, and contains abundant uric acid. Electron microscopy (EM) demonstrated that the cytosol of the reflector layer's cells is filled with densely packed spherical granules, which should be the uric acid granules. These granules are highly regular in size (∼700 nm in diameter), and exhibit a radial internal structure. X-ray diffraction (XRD) analyses revealed that an intense single peak pattern with a d-spacing value of 0.320 nm is specifically detected in the light organ, and is highly similar to the diffraction peak pattern and d-spacing value of needle-formed crystals of monosodium urate monohydrate. However, the molar ratio evaluation of uric acid to various cations (K+, Na+, Ca2+ and Mg2+) in the light organ deduced that only a few uric acid molecules were in the form of urate salts. Thus, non-salt uric acid should be the source of the diffraction signal detected in the light organ. Conclusions: In the light organ, the intense single peak diffraction signal might come from a unique needle-like uric acid form, which is different from other known structures of non-salt uric acid form. The finding of a radial structure in the granules of reflector layer implies that the spherical uric acid granules might be formed by the radial arrangement of needle-formed packing matter.


Related Articles

  • Antidiabetic Activity of Vinca rosea Extracts in Alloxan-Induced Diabetic Rats. Ahmed, Mohammed Fazil; Kazim, SyedMohammed; Ghori, Syed Safiullah; Mehjabeen, Syeda Sughra; Ahmed, Shaik Rasheed; Ali, ShaikMehboob; Ibrahim, Mohammed // International Journal of Endocrinology;2010, p1 

    The present study was carried out to evaluate the antidiabetic activity of Vinca rosea methanolic whole plant extracts in alloxan induced diabetic rats for 14 days. The methanolic whole plant extract at high dose (500 mg/kg) exhibited significant antihyperglycemice activity than whole plant...

  • Do Uric Acid Deposits in Zooxanthellae Function as Eye- Spots? Yamashita, Hiroshi; Kobiyama, Atsushi; Koike, Kazuhiko // PLoS ONE;2009, Vol. 4 Issue 7, p1 

    The symbiosis between zooxanthellae (dinoflagellate genus Symbiodinium) and corals is a fundamental basis of tropical marine ecosystems. However the physiological interactions of the hosts and symbionts are poorly understood. Recently, intracellular crystalline deposits in Symbiodinium were...

  • Biomass-derived functional porous carbons as novel electrode material for the practical detection of biomolecules in human serum and snail hemolymph. Veeramani, Vediyappan; Madhu, Rajesh; Chen, Shen-Ming; Lou, Bih-Show; Palanisamy, Jayabal; Vasantha, Vairathevar Sivasamy // Scientific Reports;5/22/2015, p10141 

    The biomass-derived activated carbons (ACs) have been prepared with high surface areas up to 793 m2 g−1 is by ZnCl2 activation at three different temperatures, viz. AC700, AC800, and AC900. The AC samples were characterized by a variety of analytical and spectroscopy techniques. The...

  • Bright cyan fluorescent protein variants identified by fluorescence lifetime screening. Goedhart, Joachim; van Weeren, Laura; Hink, Mark A.; Vischer, Norbert O. E.; Jalink, Kees; Gadella, Jr., Theodorus W. J. // Nature Methods;Feb2010, Vol. 7 Issue 2, p137 

    Optimization of autofluorescent proteins by intensity-based screening of bacteria does not necessarily identify the brightest variant for eukaryotes. We report a strategy to screen excited state lifetimes, which identified cyan fluorescent proteins with long fluorescence lifetimes (>3.7 ns) and...

  • β-Crystal in the iPP melt encapsulated by transcrystallinity and spherulites: effect of molecular weight. Liang, Yanyan; Zheng, Guoqiang; Liu, Shuangyang; Dai, Kun; Liu, Chuntai; Chen, Jingbo; Shen, Changyu // Journal of Materials Science;Mar2013, Vol. 48 Issue 6, p2326 

    The crystallization in isotactic polypropylene (iPP) melt inclusions, encapsulated by transcrystallinity and spherulites, was investigated by polarized light microscope. Generally, owing to the proceeding of crystallization in melt inclusions, a negative pressure will be built up. Up to a...

  • Thermal, Mechanical and Rheological Behavior of Poly(lactic acid)/Talc Composites. Jain, Shikha; Misra, Manjusri; Mohanty, Amar; Ghosh, Anup // Journal of Polymers & the Environment;Dec2012, Vol. 20 Issue 4, p1027 

    In the present study, influence of talc on thermal, mechanical and rheological behavior of PLA is investigated and the structure-property correlation for the PLA/talc composites is established. Poly(lactic acid)/talc composites are prepared by melt mixing of PLA with talc in twin screw extruder...

  • Characterization of Spherulites as a Lipidic Carrier for Low and High Molecular Weight Agents. Zhang, Peng; Huang, Yixian; Makhov, Alexander; Gao, Xiang; Zhang, Peijun; Li, Song // Pharmaceutical Research;Jun2013, Vol. 30 Issue 6, p1525 

    Purpose: To develop spherulite formulations to achieve high entrapment efficiency for both small and macromolecules as well as cell-type specific delivery. Methods: Spherulites of various compositions were prepared, and lipid-PEG was incorporated through post-insertion. Calcein and FITC-labeled...

  • Important Matters of Non-Isothermal Crystallization Method. Xiaocan Zhang; Lu Zhou; Qiang Liu; Qiong Zhou; Singfield, Kathy L. // Applied Mechanics & Materials;2014, Vol. 722, p9 

    Non-isothermal crystallization method was performed for pure PLLA and a blend of 50/50 wt% PEO/PLLA samples. The spherulite radial growth rate was calculated and compared to what was acquired using the isothermal crystallization method. It is found that both the fitting order and the decimal...

  • Partially bio-based thermoplastic elastomers by physical blending of poly(hydroxyalkanoate)s and poly(ethylene-co-vinyl acetate). Ma, P.; Cai, X.; Chen, M.; Dong, W.; Lemstra, P. J. // Express Polymer Letters;2014, Vol. 8 Issue 7, p517 

    Partially bio-based thermoplastic elastomers (bio-TPE) were designed and prepared by physical blending a commercial grade poly(hydroxyalkanoate)s (PHBM, Metabolix) and poly(ethylene-co-vinyl acetate) (EVA). The PHBM is miscible with EVA90 which has a vinyl acetate (VA) content of 90 wt% while it...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics