Arthropod defensin

Arthropod defensin
Structure of insect defensin A.[1]
Identifiers
Symbol Defensin_2
Pfam PF01097
InterPro IPR001542
PROSITE PDOC00356
SCOP 1ica
TCDB 1.C.47
OPM family 61
OPM protein 1l4v

Arthropod defensins are a family of insect and scorpion cysteine-rich antibacterial peptides, primarily active against Gram-positive bacteria[2][3][4][5][6]. All these peptides range in length from 38 to 51 amino acids. There are six conserved cysteines all involved in intrachain disulfide bonds.

A schematic representation of peptides from the arthropod defensin family is shown below.

           +----------------------------+
           |                            |
         xxCxxxxxxxxxxxxxxCxxxCxxxxxxxxxCxxxxxCxCxx
                          |   |               | |
                          +---|---------------+ |
                              +-----------------+

'C': conserved cysteine involved in a disulfide bond.

Although low level sequence similarities have been reported[2] between the arthropod defensins and mammalian defensins, the topological arrangement of the disulfide bonds as well as the tertiary structure[7] are completely different in the two families.

Notes

  1. ^ Cornet B, Bonmatin JM, Hetru C, Hoffmann JA, Ptak M, Vovelle F (May 1995). "Refined three-dimensional solution structure of insect defensin A". Structure 3 (5): 435–48. doi:10.1016/S0969-2126(01)00177-0. PMID 7663941. 
  2. ^ a b Dunbar B, Lambert J, Keppi E, Wicker C, Lepage P, Hoffmann J, Fothergill J, Dimarcq JL, Reichhart JM, Van Dorsselaer A (1989). "Insect immunity: isolation from immune blood of the dipteran Phormia terranovae of two insect antibacterial peptides with sequence homology to rabbit lung macrophage bactericidal peptides". Proc. Natl. Acad. Sci. U.S.A. 86 (1): 262–266. doi:10.1073/pnas.86.1.262. PMC 286444. PMID 2911573. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=286444. 
  3. ^ Kobayashi K, Fujiwara S, Imai J, Fujiwara M, Yaeshima T, Kawashima T (1990). "A potent antibacterial protein in royal jelly. Purification and determination of the primary structure of royalisin". J. Biol. Chem. 265 (19): 11333–11337. PMID 2358464. 
  4. ^ Yamada K, Natori S (1993). "Purification, sequence and antibacterial activity of two novel sapecin homologues from Sarcophaga embryonic cells: similarity of sapecin B to charybdotoxin". Biochem. J. 291: 275–279. PMC 1132513. PMID 8471044. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1132513. 
  5. ^ Cociancich S, Bulet P, Hoffmann JA, Hetru C, Lambert J, Hoffmann D, Dimarcq JL, Reichhart JM (1991). "Insect immunity. Isolation from a coleopteran insect of a novel inducible antibacterial peptide and of new members of the insect defensin family". J. Biol. Chem. 266 (36): 24520–24525. PMID 1761552. 
  6. ^ Cociancich S, Bulet P, Hoffmann JA, Hegy G, Hetru C, Reuland M, Sauber F, Bischoff R, Van Dorsselaer A (1992). "A novel insect defensin mediates the inducible antibacterial activity in larvae of the dragonfly Aeschna cyanea (Paleoptera, Odonata)". Eur. J. Biochem. 209 (3): 977–984. doi:10.1111/j.1432-1033.1992.tb17371.x. PMID 1425705. 
  7. ^ Natori S, Kohda D, Hanzawa H, Shimada I, Kuzuhara T, Komano H, Inagaki F, Arata Y (1990). "1H nuclear magnetic resonance study of the solution conformation of an antibacterial protein, sapecin". FEBS Lett. 269 (2): 413–420. doi:10.1016/0014-5793(90)81206-4. PMID 2401368. 

Further reading

References