Analytical and Bioanalytical Chemistry

, Volume 409, Issue 27, pp 6415–6420 | Cite as

The hypertrehalosemic neuropeptides of cicadas are structural isomers—evidence by ion mobility mass spectrometry

Research Paper

Abstract

It has been known for more than 20 years that the neurosecretory glands of the cicadas, the corpora cardiaca, synthesize two isobaric peptides with hypertrehalosemic activity. Both decapeptides have exactly the same amino acid sequence (pGlu-Val-Asn-Phe-Ser-Pro-Ser-Trp-Gly-Asn-NH2) and mass but differ in their retention time in reversed-phase liquid chromatography. A synthetic peptide with the same sequence elutes together with the second more hydrophobic peptide peak of the natural cicada extract. It is not clear what modification is causing the described observations. Therefore, in the current study, ion mobility separation in conjunction with high-resolution mass spectrometry was used to investigate this phenomenon as it was sensitive to changes in conformation. It detected different drift times in buffer gas for both the intact peptides and some of their fragment ions. Based on the ion mobility and fragment ion intensity of the corresponding ions, it is concluded that the region Pro6-Ser7-Trp8 contains a structural feature differing from the L-amino acids present in the known peptide. Whether the conformer is the result of racemization or other biochemical processes needs to be further investigated.

Keywords

Ion mobility mass spectrometry AKH Conformation Isomer 

Abbreviations

AKH

Adipokinetic hormone

DT

Drift time

IMS

Ion mobility separation

MALDI

Matrix-assisted laser desorption

MS

Mass spectrometry

RP-LC

Reversed-phase liquid chromatography

RT

Retention time

Notes

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

All applicable international, national and/or institutional guidelines for the care and use of animals were followed. This article does not contain any studies with human participants performed by any of the authors.

Supplementary material

216_2017_583_MOESM1_ESM.pdf (816 kb)
ESM 1 ᅟ (PDF 805 kb)

References

  1. 1.
    Snyder SH. Brain peptides as neurotransmitters. Science. 1980;209:976–83.CrossRefGoogle Scholar
  2. 2.
    Gäde G, Hoffmann KH, Spring JH. Hormonal regulation in insects: facts, gaps, and future directions. Physiol Rev. 1997;77:963–1032.Google Scholar
  3. 3.
    Gäde G. Regulation of intermediary metabolism and water balance of insects by neuropeptides. Annu Rev Entomol. 2004;49:93–113.CrossRefGoogle Scholar
  4. 4.
    Gäde G. Peptides of the adipokinetic hormone red pigment-concentrating hormone family. A new take on biodiversity. Ann N Y Acad Sci. 2009;1163:125–36.CrossRefGoogle Scholar
  5. 5.
    Gäde G, Šimek P, Marco HG. Two novel tyrosine-containing peptides (Tyr4) of the adipokineic hormone family in beetles of the families Coccinellidae and Silphidae. Amino Acids. 2015;47:2323–33.CrossRefGoogle Scholar
  6. 6.
    Gäde G, Šimek P, Marco HG. A novel adipokinetic peptide from the corpus cardiacum of the primitive caeliferan pygmy grasshopper Tetrix subulata (Caelifera, Tetrigidae). Peptides. 2015;68:43–9.CrossRefGoogle Scholar
  7. 7.
    Gäde G, Janssens MPE. Cicadas contain novel members of the AKH/RPCH family peptides with hypertrehalosaemic activity. Biol Chem Hoppe Seyler. 1994;375:803–9.CrossRefGoogle Scholar
  8. 8.
    Raina A, Pannell L, Kochansky J, Jaffe H. Primary structure of a novel neuropeptide isolated from the corpora cardiaca of periodical cicadas having adipokinetic and hypertrehalosemic activities. Insect Biochem Mol Biol. 1995;25:929–32.CrossRefGoogle Scholar
  9. 9.
    Veenstra JA, Hagedorn HH. Isolation of two AKH-related peptides from cicadas. Arch Insect Biochem Physiol. 1995;29:391–6.CrossRefGoogle Scholar
  10. 10.
    Lanucara F, Holman SW, Gray CJ, Eyers CE. The power of ion mobility-mass spectrometry for structural characterization and the study of conformational dynamics. Nat Chem. 2014;6:281–94.CrossRefGoogle Scholar
  11. 11.
    Distler U, Kuharev J, Navarro P, Levin Y, Schild H, Tenzer J. Drift time-specific collision energies enable deep-coverage data- independent acquisition proteomics. Nat Methods. 2014;11:167–70.CrossRefGoogle Scholar
  12. 12.
    Gäde G, Goldsworthy GJ, Kegel G, Keller R. Single step purification of locust adipokinetic hormones I and II by reversed-phase high-performance liquid chromatography and the amino-acid composition of the hormone II. Hoppe-Seyler’s Z Physiol Chem. 1984;365:393–8.CrossRefGoogle Scholar
  13. 13.
    König S, Albers C, Gäde G. Mass spectral signature for insect adipokinetic hormones. Rapid Commun Mass Spectrom. 2005;19:3021–4.CrossRefGoogle Scholar
  14. 14.
    Bai L, Romanova EV, Sweedler JV. Distinguishing endogenous D-amino acid-containing neuropeptides in individual neurons using tandem mass spectrometry. Anal Chem. 2011;83:2794–800.CrossRefGoogle Scholar
  15. 15.
    Chamond N, Gregoire C, Coatnoan N, Rougeot C, Freitas-Junior LC, da Silveira JF, et al. Biochemical characterization of proline racemases from the human protozoan parasite Trypanosoma cruzi and definition of putative protein signatures. J Biol Chem. 2003;278:15484–94.CrossRefGoogle Scholar
  16. 16.
    Kimura T, Hamase K, Miyoshi Y, Yamamoto R, Yasuda K, Mita M, et al. Chiral amino acid metabolomics for novel biomarker screening in the prognosis of chronic kidney disease. Sci Rep. 2016;6:26137.CrossRefGoogle Scholar
  17. 17.
    Schmid FX. Prolyl isomerases. Adv Protein Chem. 2002;59:243–82.CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  1. 1.Core Unit Proteomics, Interdisciplinary Center for Clinical ResearchUniversity of MünsterMünsterGermany
  2. 2.Department of Biological SciencesUniversity of Cape TownCape TownSouth Africa

Personalised recommendations