Kallidin

Kallidin belongs to the family kinins, which are the peptide hormones.^[1] Kallidin is a decapeptide whose sequence is H-Lys-Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg-OH. Removal of the N-terminal lysine by Factor XII ^[2], or to a leser extent aminopeptidase^[3] yields the potently bioactive bradykinin molecule.

Kallidin

Names
IUPAC name L-Lysyl-L-arginyl-L-prolyl-L-prolyl-glycyl-L-phenylalanyl-L-seryl-L-prolyl-L-phenylalanyl-L-arginine
Identifiers
CAS Number	342-10-9 Y
3D model (JSmol)	Interactive image
ChemSpider	4470640 Y
ECHA InfoCard	100.005.853
IUPHAR/BPS	650
MeSH	Kallidin
PubChem CID	5311111
UNII	0T8T4A440G Y
CompTox Dashboard (EPA)	DTXSID40895018
InChI InChI=1S/C56H85N17O12/c57-24-8-7-18-36(58)46(76)67-37(19-9-25-63-55(59)60)51(81)73-29-13-23-44(73)53(83)72-28-11-21-42(72)49(79)65-32-45(75)66-39(30-34-14-3-1-4-15-34)47(77)70-41(33-74)52(82)71-27-12-22-43(71)50(80)69-40(31-35-16-5-2-6-17-35)48(78)68-38(54(84)85)20-10-26-64-56(61)62/h1-6,14-17,36-44,74H,7-13,18-33,57-58H2,(H,65,79)(H,66,75)(H,67,76)(H,68,78)(H,69,80)(H,70,77)(H,84,85)(H4,59,60,63)(H4,61,62,64)/t36-,37-,38-,39-,40-,41-,42-,43-,44-/m0/s1 Y Key: FYSKZKQBTVLYEQ-FSLKYBNLSA-N Y InChI=1/C56H85N17O12/c57-24-8-7-18-36(58)46(76)67-37(19-9-25-63-55(59)60)51(81)73-29-13-23-44(73)53(83)72-28-11-21-42(72)49(79)65-32-45(75)66-39(30-34-14-3-1-4-15-34)47(77)70-41(33-74)52(82)71-27-12-22-43(71)50(80)69-40(31-35-16-5-2-6-17-35)48(78)68-38(54(84)85)20-10-26-64-56(61)62/h1-6,14-17,36-44,74H,7-13,18-33,57-58H2,(H,65,79)(H,66,75)(H,67,76)(H,68,78)(H,69,80)(H,70,77)(H,84,85)(H4,59,60,63)(H4,61,62,64)/t36-,37-,38-,39-,40-,41-,42-,43-,44-/m0/s1 Key: FYSKZKQBTVLYEQ-FSLKYBNLBR
SMILES O=C(N[C@H](C(=O)N[C@H](C(=O)O)CCC/N=C(\N)N)Cc1ccccc1)[C@H]5N(C(=O)[C@@H](NC(=O)[C@@H](NC(=O)CNC(=O)[C@H]3N(C(=O)[C@H]2N(C(=O)[C@@H](NC(=O)[C@@H](N)CCCCN)CCC/N=C(\N)N)CCC2)CCC3)Cc4ccccc4)CO)CCC5
Properties
Chemical formula	C56H85N17O12
Molar mass	1188.403 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Effects of Kinins

Kallidin is a bioactive kinin peptide formed in response to injury from kininogen precursors through the action of kallikreins.^[4] Like all kinins, kallidin, the deca-peptide, plays an important role in several body pathologies. Kinins can regulate the blood pressure by increasing the level of vasopressor substances.^[1][5] They can also bind to the B₁ and B₂ cell surface receptors, which are G-protein coupled receptors.^[6] The mediation of the B₁ receptors by des-Arg kinins as agonists can be expressed in several medical issues, such as cancer and trauma.^[5] By binding to the B₂ receptors, kinins, endogenous agonists, can regulate the vasodilatation and bronchioconstriction.^[1]

Chemical Mechanisms

Since kinins are peptides, they can be cleaved by the peptidases. Peptidases such as the serine peptidases, carboxypeptidase N and carboxypeptidase M cleave kinins into des-Arg-bradykinin and Lys-des-Arg-bradykinin.^[7][8]

Clarification

Kallidin is identical to bradykinin with an additional lysine residue added at the N-terminal end and signals through the bradykinin receptor.^{[citation needed]}

Despite exhibiting similar functions and reactivities, kinins can be differentiated by combining an amino-terminal-directed radioimmunoassay with a carboxy-terminal-directed radioimmunoassay in combination with HPLC.^[1]

See also

• Kinin
• Bradykinin