 |
Claims  |
|
|
What is claimed is:
1. A cyclic peptide comprising an amphiphilic anti-parallel .beta.-sheet
region, a loop region and a .beta.-turn region, wherein:
the cyclic peptide has a net positive charge at physiological pH;
at least one amino acid residue in either the loop region or the
.beta.-turn region is a basic amino acid,
wherein the peptide has antimicrobial activity against E. coil, Pseudomonas
aeruginosa, methicillin-resistant Staphylococcus aureus or
vancomycin-resistant Enterococcus faecium
and said cyclic peptide is cyclized by way of backbone atoms.
2. The cyclic peptide of claim 1, wherein the .beta.-turn region is a four
amino acid residue peptide segment selected from the group consisting of:
______________________________________
ARTE (SEQ ID NO: 1);
GFRE (SEQ ID NO: 2);
GNRG (SEQ ID NO: 3);
LPRE (SEQ ID NO: 4);
RFGE (SEQ ID NO: 5);
SYRE (SEQ ID NO: 6);
AFLK (SEQ ID NO: 7);
AGIR (SEQ ID NO: 8);
APRV (SEQ ID NO: 9);
FQNR (SEQ ID NO: 10);
GFRS (SEQ ID NO: 11);
HFGG (SEQ ID NO: 12);
IFGR (SEQ ID NO: 13);
IGGR (SEQ ID NO: 14);
IPIR (SEQ ID NO: 15);
IRGV (SEQ ID NO: 16);
ISGR (SEQ ID NO: 17);
IWGR (SEQ ID NO: 18);
LWGR (SEQ ID NO: 19);
RFPY (SEQ ID NO: 20);
RFYL (SEQ ID NO: 21);
RGFL (SEQ ID NO: 22);
RGGI (SEQ ID NO: 23);
RGWI (SEQ ID NO: 24);
RGWV (SEQ ID NO: 25);
RIGA (SEQ ID NO: 26);
RIPA (SEQ ID NO: 27);
RIPI (SEQ ID NO: 28);
RIPV (SEQ ID NO: 29);
RLVF (SEQ ID NO: 30);
RTSS (SEQ ID NO: 31);
TTRT (SEQ ID NO: 32);
VPIR (SEQ ID NO: 33);
VWGR (SEQ ID NO: 34);
GPRI (SEQ ID NO: 35);
GPRV (SEQ ID NO: 36);
GRAV (SEQ ID NO: 37);
GRPV (SEQ ID NO: 38);
INRG (SEQ ID NO: 39);
LLNR (SEQ ID NO: 40);
LNGR (SEQ ID NO: 41);
LPNR (SEQ ID NO: 42);
RNGG (SEQ ID NO: 43);
RNPL (SEQ ID NO: 44);
YQGR (SEQ ID NO: 45);
FQHR (SEQ ID NO: 46);
KGRE (SEQ ID NO: 47);
RARG (SEQ ID NO: 48);
RRTE (SEQ ID NO: 49);
IRGR (SEQ ID NO: 50);
KGHL (SEQ ID NO: 51);
RFHL (SEQ ID NO: 52);
RKSG (SEQ ID NO: 53);
RPRV (SEQ ID NO: 54);
RRAL (SEQ ID NO: 55);
RRFS (SEQ ID NO: 56);
RRGS (SEQ ID NO: 57);
RSRG (SEQ ID NO: 58);
RSTR (SEQ ID NO: 59);
RTGR (SEQ ID NO: 60);
RTRG (SEQ ID NO: 61);
YRGR (SEQ ID NO: 62);
RKNG (SEQ ID NO: 63);
RNKG (SEQ ID NO: 64);
KRRE (SEQ ID NO: 65);
RKRG (SEQ ID NO: 66);
RRRF (SEQ ID NO: 67); and
RRTR (SEQ ID NO: 68).
______________________________________
3. The cyclic peptide of claim 1 wherein the loop region is a three or four
amino acid residue peptide sequence selected from the group consisting of:
______________________________________
ARTE (SEQ ID NO: 1);
GFRE (SEQ ID NO: 2);
GNRG (SEQ ID NO: 3);
LPRE (SEQ ID NO: 4);
RFGE (SEQ ID NO: 5);
SYRE (SEQ ID NO: 6);
AFLK (SEQ ID NO: 7);
AGIR (SEQ ID NO: 8);
APRV (SEQ ID NO: 9);
FQNR (SEQ ID NO: 10);
GFRS (SEQ ID NO: 11);
HFGG (SEQ ID NO: 12);
IFGR (SEQ ID NO: 13);
IGGR (SEQ ID NO: 14);
IPIR (SEQ ID NO: 15);
IRGV (SEQ ID NO: 16);
ISGR (SEQ ID NO: 17);
IWGR (SEQ ID NO: 18);
LWGR (SEQ ID NO: 19);
RFPY (SEQ ID NO: 20);
RFYL (SEQ ID NO: 21);
RGFL (SEQ ID NO: 22);
RGGI (SEQ ID NO: 23);
RGWI (SEQ ID NO: 24);
RGWV (SEQ ID NO: 25);
RIGA (SEQ ID NO: 26);
RIPA (SEQ ID NO: 27);
RIPI (SEQ ID NO: 28);
RIPV (SEQ ID NO: 29);
RLVF (SEQ ID NO: 30);
RTSS (SEQ ID NO: 31);
TTRT (SEQ ID NO: 32);
VPIR (SEQ ID NO: 33);
VWGR (SEQ ID NO: 34);
GPRI (SEQ ID NO: 35);
GPRV (SEQ ID NO: 36);
GRAV (SEQ ID NO: 37);
GRPV (SEQ ID NO: 38);
INRG (SEQ ID NO: 39);
LLNR (SEQ ID NO: 40);
LNGR (SEQ ID NO: 41);
LPNR (SEQ ID NO: 42);
RNGG (SEQ ID NO: 43);
RNPL (SEQ ID NO: 44);
YQGR (SEQ ID NO: 45);
FQHR (SEQ ID NO: 46);
KGRE (SEQ ID NO: 47);
RARG (SEQ ID NO: 48);
RRTE (SEQ ID NO: 49);
IRGR (SEQ ID NO: 50);
KGHL (SEQ ID NO: 51);
RFHL (SEQ ID NO: 52);
RKSG (SEQ ID NO: 53);
RPRV (SEQ ID NO: 54);
RRAL (SEQ ID NO: 55);
RRFS (SEQ ID NO: 56);
RRGS (SEQ ID NO: 57);
RSRG (SEQ ID NO: 58);
RSTR (SEQ ID NO: 59);
RTGR (SEQ ID NO: 60);
RTRG (SEQ ID NO: 61);
YRGR (SEQ ID NO: 62);
RKNG (SEQ ID NO: 63);
RNKG (SEQ ID NO: 64);
KRRE (SEQ ID NO: 65);
RKRG (SEQ ID NO: 66);
RRRF (SEQ ID NO: 67);
RRTR (SEQ ID NO: 68);
GFGE (SEQ ID NO: 70);
GSGE (SEQ ID NO: 71);
IAGE (SEQ ID NO: 72);
LPLE (SEQ ID NO: 73);
PWSE (SEQ ID NO: 74);
VSGE (SEQ ID NO: 75);
YSTE (SEQ ID NO: 76);
IGGV (SEQ ID NO: 77);
IPIS (SEQ ID NO: 78);
IWGV (SEQ ID NO: 79);
VWGA (SEQ ID NO: 80);
VWGI (SEQ ID NO: 81);
VWGV (SEQ ID NO: 82);
INGV (SEQ ID NO: 83);
TNGG (SEQ ID NO: 84);
VNGA (SEQ ID NO: 85);
VNGV (SEQ ID NO: 86);
WNMG (SEQ ID NO: 87);
GPQI (SEQ ID NO: 88);
VPW (SEQ ID NO: 89);
VGW (SEQ ID NO: 90);
LPF (SEQ ID NO: 91);
RGW (SEQ ID NO: 92);
WAL (SEQ ID NO: 93);
VRW (SEQ ID NO: 94); and
VRL (SEQ ID NO: 95).
______________________________________
4. A cyclic peptide having antimicrobiol activity against E. coli,
Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus or
vancomycin-resistant entereococcus faecium having the formula:
##STR9##
wherein m=0,1,2 and n=0,1 with the proviso that when m=2, n=0; X.sub.21,
X.sub.22, X.sub.24, x.sub.25, X.sub.27 and X.sub.28 are each independently
present or absent;
X.sub.7 and X.sub.14 are either both present or both absent;
X.sub.8 and X.sub.13 are either both present or both absent;
X.sub.2, X.sub.3, X.sub.4, X.sub.5, X.sub.7, X.sub.8, X.sub.13, X.sub.14,
X.sub.16, X.sub.17, X.sub.18 X.sub.19, X.sub.20, X.sub.22, X.sub.27 and
X.sub.28 are each independently a hydrophobic amino acid, a hydrophilic
amino acid or a small amino acid, with the provisos that (i) when X.sub.2
is a hydrophobic amino acid X.sub.7, X.sub.14, X.sub.19, X.sub.21, and
X.sub.28 are each independently a hydrophobic amino acid or a small amino
acid and X.sub.3, X.sub.8, X.sub.13, X.sub.18, X.sub.22 and X.sub.27 are
each independently a hydrophilic amino acid or a small amino acid; and
(ii) when X.sub.2 is a hydrophilic amino acid X.sub.7, X.sub.14, X.sub.19,
X.sub.21 and X.sub.28 are each independently a hydrophilic amino acid or a
small amino acid and X.sub.3, X.sub.8, X.sub.13, X.sub.18, X.sub.22 and
X.sub.27 are each independently a hydrophobic amino acid or a small amino
acid;
X.sub.23, X.sub.24, X.sub.25 and X.sub.26 taken together are a loop;
Z.sub.1, Z.sub.6, Z.sub.15 and Z.sub.20 are each independently a
hydrophilic amino acid, a small amino acid or a cysteine-like amino acid;
X.sub.9, X.sub.10, X.sub.11 and X.sub.12 taken together are a .beta.-turn;
at least one of X.sub.9, X.sub.10, X.sub.11, X.sub.12, X.sub.23, X.sub.24,
X.sub.25 or X.sub.26 is a basic amino acid; and
the peptide has a net positive charge at physiological pH.
5. The cyclic peptide of claim 4 wherein the peptide is selected from the
group consisting of:
______________________________________
cyclo(SVRGFRVRGF) (SEQ ID NO: 100);
cyclo(SVR*GFSVR*GF) (SEQ ID NO: 101);
cyclo(FVRSYVLRSV) (SEQ ID NO: 102);
cyclo(FVPRYVLPRV) (SEQ ID NO: 103);
cyclo(YVRGFVFGRV) (SEQ ID NO: 104);
cyclo(CVRRYCLWRGV) (SEQ ID NO: 105);
cycld(CVTRYCLWRGV) (SEQ ID NO: 106);
cyclo(CVRTYCLRGW) (SEQ ID NO: 107);
cyclo(CVPRYCLWRGV) (SEQ ID NO: 108);
cyclo(CVRRYCLGRW) (SEQ ID NO: 109);
cyclo(CVRRYCLGW) (SEQ ID NO: 110);
cyclo(CVR*RYCLWRGW) (SEQ ID NO: 111);
cyclo(CRRRFCYDLWRGV-Dpr-V)
(SEQ ID NO: 112);
cyclo(CV-Dpr-RPRFDYCLWRGV)
(SEQ ID NO: 113);
cyclo(CV-Dpr-RPRFDYCLPRW)
(SEQ ID NO: 114);
cyclo(Dpr-VDRPRF-Dpr-YDLWRGV)
(SEQ ID NO: 115);
cyclo(SVOGFSVOGF) (SEQ ID NO: 116);
cyclo(FVGOYVLGOV) (SEQ ID NO: 117);
cyclo(FVGOYVWPOV) (SEQ ID NO: 118);
cyclo(YVRGFVFGOV) (SEQ ID NO: 119);
cyclo(YVOGFVFOGV) (SEQ ID NO: 120);
cyclo(CYSOYCLWOGV) (SEQ ID NO: 121);
cyclo(CVPOYCLWOGV) (SEQ ID NO: 122);
cyclo(CVOOYCLWOGF) (SEQ ID NO: 123);
cyclo(SVKGFKVKGF) (SEQ ID NO: 124);
cyclo(FVGKYVLGKV) (SEQ ID NO: 125);
cyclo(FVGKYVWPKV) (SEQ ID NO: 126);
cyclo(YVKGFVFGKV) (SEQ ID NO: 127);
cyclo(YAKGFVFGKV) (SEQ ID NO: 128);
cyclo(CVKKYCLWKGV) (SEQ ID NO: 129);
cyclo(CVSKYCLWKGV) (SEQ ID NO: 130);
cyclo(CVSKYCLGW) (SEQ ID NO: 131);
cyclo(CVPKYCLKGW) (SEQ ID NO: 132);
cyclo(CGFRSCVGRWL) (SEQ ID NO: 133);
cyclo(CIRGVCLWKGY) (SEQ ID NO: 134);
cyclo(CGFRSCVGRW) (SEQ ID NO: 135); and
cyclo(CRGVCWRGY) (SEQ ID NO: 136).
______________________________________
6. The cyclic peptide of claim 4 having the formula:
##STR10##
wherein m=2; .parallel. designates a disulfide linkage;
X.sub.21, X.sub.22, X.sub.24, X.sub.25, X.sub.27 and X.sub.28 are each
independently present or absent;
X.sub.2 is a hydrophobic amino acid;
X.sub.3, X.sub.18, X.sub.22 and X.sub.27 are each independently a
hydrophilic amino acid or a small amino acid;
X.sub.4, X.sub.17, X.sub.19, X.sub.21 and X.sub.28 are each independently a
hydrophobic amino acid or a small amino acid;
X.sub.23, X.sub.24, X.sub.25 and X.sub.26 taken together are a loop;
Z.sub.1, Z.sub.6, Z.sub.15 and Z.sub.20 are each cysteine, homocysteine or
penicillamine;
x.sub.9, X.sub.10, X.sub.11 and X.sub.12 taken together are a .beta.-turn;
at least one of X.sub.9, X.sub.10, X.sub.11, X.sub.12, X.sub.23, X.sub.24,
X.sub.25 or X.sub.26 is a basic amino acid; and
the peptide has a net positive charge at physiological pH.
7. The cyclic peptide of claim 4 having the formula:
##STR11##
wherein .parallel. designates a disulfide linkage; X.sub.21, X.sub.22,
X.sub.24, X.sub.25, X.sub.27 and X.sub.28 are each independently present
or absent;
X.sub.2 is a hydrophobic amino acid;
X.sub.3, X.sub.18, X.sub.22 and X.sub.27 are each independently a
hydrophilic amino acid or a small amino acid;
X.sub.4, X.sub.17, X.sub.19, X.sub.21 and X.sub.28 are each independently a
hydrophobic amino acid or a small amino acid;
X.sub.23, X.sub.24, X.sub.25 and X.sub.26 taken together are a loop;
Z.sub.1, Z.sub.6, Z.sub.15 and Z.sub.20 are each cysteine, homocysteine or
penicillamine;
X.sub.9, X.sub.10, X.sub.11 and X.sub.12 taken together are a .beta.-turn;
at least one of X.sub.9, X.sub.10, X.sub.11, X.sub.12, X.sub.23, X.sub.24,
X.sub.25 or X.sub.26 is a basic amino acid; and
the peptide has a net positive charge at physiological pH.
8. The cyclic peptide of claim 7 wherein the peptide is selected from the
group consisting of:
______________________________________
cyclo(CLRYCRRRFCVRFCLWF)
(SEQ ID NO: 140);
cyclo(CLRYCRR*FCVRFCLWF)
(SEQ ID NO: 141);
cyclo(CLRYCRPFCVSYCVRWF)
(SEQ ID NO: 142);
cyclo(CLRYCRIPICVRFCVPRW)
(SEQ ID NO: 143);
cyclo(CLRYCRF*PFCVRFCLSRW)
(SEQ ID NO: 144);
cyclo(CL-Dpr-YCRRRFCVDYCVRGW)
(SEQ ID NO: 145);
cyclo(CL-Dpr-YCVRRFCVDYCVGW)
(SEQ ID NO: 146); and
cyclo(CL-Dpr-YCRSRFCVDYCVGW)
(SEQ ID NO: 147).
______________________________________
9. The cyclic peptide of claim 4 having the structure:
##STR12##
wherein .parallel. designates a disulfide linkage; X.sub.21, X.sub.22,
X.sub.24, X.sub.25, X.sub.27 and X.sub.28 are each independently present
or absent;
X.sub.2 is a hydrophobic amino acid;
X.sub.22 and X.sub.27 are each independently a hydrophilic amino acid or a
small amino acid;
X.sub.19, X.sub.21 and X.sub.28 are each independently a hydrophobic amino
acid or a small amino acid;
X.sub.23, X.sub.24, X.sub.25 and X.sub.26 taken together are a loop;
Z.sub.1, Z.sub.6, Z.sub.15 and Z.sub.20 are each independently cysteine,
homocysteine or penicillamine;
X.sub.9, X.sub.10, X.sub.11 and X.sub.12 taken together are a .beta.-turn;
at least one of X.sub.9, X.sub.10, X.sub.11, X.sub.12, X.sub.23, X.sub.24,
X.sub.25 or X.sub.26 is a basic amino acid; and
the peptide has a net positive charge at physiological pH.
10. The cyclic peptide of claim 9 wherein the peptide is selected from the
group consisting of:
______________________________________
cyclo(CYCRRRFCVCVL) (SEQ ID NO: 150);
cyclo(CYCRRRFCVCVWY) (SEQ ID NO: 151);
cyclo(CYCRGRFCVRW) (SEQ ID NO: 152);
cyclo(CVCFR*R*RCYCLWV)
(SEQ ID NO: 153);
cyclo(CYCRRRFCVCVRL) (SEQ ID NO: 154);
cyclo(CVCFR*R*RCYCLRV)
(SEQ ID NO: 155);
cyclo(CYCRRRFCVCIFGR)
(SEQ ID NO: 156);
cyclo(CYCRRRFCVCISGR)
(SEQ ID NO: 157);
cyclo(CYCRRRFCVCIRGV)
(SEQ ID NO: 158);
cyclo(CYCRRRFCVCIWGR)
(SEQ ID NO: 159);
cyclo(CYCRRRFCVCRFPY)
(SEQ ID NO: 160);
cyclo(CYCRRRFCVCRGFL)
(SEQ ID NO: 161);
cyclo(CYCRRRFCVCRGWV)
(SEQ ID NO: 162);
cyclo(CYCRRRFCVCRGWI)
(SEQ ID NO: 163);
cyclo(CYCRRRFCVCRIPA)
(SEQ ID NO: 164);
cyclo(CYCRRRFCVCYRGR)
(SEQ ID NO: 165);
cyclo(CYCRRRFCVCRLVF)
(SEQ ID NO: 166);
cyclo(CYCRRRFCVCVR-Cha)
(SEQ ID NO: 167);
cyclo(CYCRPRFCVCVR-Cha)
(SEQ ID NO: 168);
cyclo(CYCFRRFCVCVR-Cha)
(SEQ ID NO: 169);
cyclo(CYCRRRFCVCVRG-Cha)
(SEQ ID NO: 170);
cyclo(CYCRRRFCVCVRW) (SEQ ID NO: 171);
cyclo(CYCRPRFCVCVRW) (SEQ ID NO: 172);
cyclo(CYCRSRFCVCVR-Cha)
(SEQ ID NO: 173);
cyclo(CYCVRRFCVCVRW) (SEQ ID NO: 174);
cyclo(CFCVOOFCVCFOV) (SEQ ID NO: 175);
cyclo(CFCVOOYCVCVOW) (SEQ ID NO: 176);
cyclo(CFCOPO*YCVCVO-Cha)
(SEQ ID NO: 177);
cyclo(CFCVOTYCVCVO-Cha)
(SEQ ID NO: 178);
cyclo(CFCV-MeGly-O*YCVCYOV)
(SEQ ID NO: 179);
cyclo(CYCOO*OFCVCVOWL)
(SEQ ID NO: 180);
cyclo(CYCOOOFCVCVOWL)
(SEQ ID NO: 181);
cyclo(CYCRGRFCVCVGRWL)
(SEQ ID NO: 182);
cyclo(CVCFR*R*RCYCLWRGV)
(SEQ ID NO: 183);
cyclo(CVCFR*R*RCYCLWGRV)
(SEQ ID NO: 184);
cyclo(CYCRRRFCVCVGRWL) (all D)
(SEQ ID NO: 185);
cyclo(CYCRPRFCVCVGRWL)
(SEQ ID NO: 186);
cyclo(CVCFRPRCYCLWRGV)
(SEQ ID NO: 187);
cyclo(CVCFPRRCYCLWRGV)
(SEQ ID NO: 188);
cyclo(CVCVGPRCYCLRGW)
(SEQ ID NO: 189);
cyclo(CYCRRRFCVCVRWL)
(SEQ ID NO: 190);
cyclo(CYCRRRFCVCVRGW)
(SEQ ID NO: 191);
cyclo(CYCRRRFCVCWRGV)
(SEQ ID NO: 192);
cyclo(CYCRPRFCVCWGRV)
(SEQ ID NO: 193);
cyclo(CYCRRRFCVCVRGW)
(SEQ ID NO: 194);
cyclo(CVCRPRWCYCLWSV)
(SEQ ID NO: 195);
cyclo(CYCRRRFCVCVGRWL)
(SEQ ID NO: 196);
cyclo(CYCRR*RFCVCVGRWL)
(SEQ ID NO: 197);
cyclo(CYCSRRYCVCYPRV)
(SEQ ID NO: 198);
cyclo(CYCVRRYCVCYGRWV)
(SEQ ID NO: 199);
cyclo(CYCGR*RYCVCYARWV)
(SEQ ID NO: 200);
cyclo(CVCRSRFCYCLWRGV)
(SEQ ID NO: 201);
cyclo(CVCRPRFCYCLWRGV)
(SEQ ID NO: 202);
cyclo(CVCYRFRCYCVWRGF)
(SEQ ID NO: 203);
cyclo(CYCRPRFCVCVGRPGWL)
(SEQ ID NO: 204);
cyclo(CYCRPRFCVCVGRGWL)
(SEQ ID NO: 205);
cyclo(CYCRGRFCVCVRGGRV)
(SEQ ID NO: 206);
cyclo(CYCVRRYCVCFGWARV)
(SEQ ID NO: 207);
cyclo(CYCRPRFCVCVGRRGWL)
(SEQ ID NO: 208);
cyclo(CYCRPRFCVCVGRRGGL)
(SEQ ID NO: 209);
cyclo(CYCRRRFCVCVGRRGGRL)
(SEQ ID NO: 210);
cyclo(CYCRGRFCVCVGRGGWRL)
(SEQ ID NO: 211);
cyclo(CYCRGRFCVCVGRRGLR-Cha)
(SEQ ID NO: 212);
cyclo(CYCRGRFCVCVGRRGWRL)
(SEQ ID NO: 213);
cyclo(CYCRPRFCVCVGRGRWRL)
(SEQ ID NO: 214);
cyclo(CYCRTRFCVCVGRRGWRL)
(SEQ ID NO: 215);
cyclo(CFCVRRFCVCFRV) (SEQ ID NO: 216);
cyclo(CFCRPRYCVCVR-Cha)
(SEQ ID NO: 217);
cyclo(CFCRF*PYCVCVR-Cha)
(SEQ ID NO: 218);
cyclo(CFCVTRYCVCVR-Cha)
(SEQ ID NO: 219);
cyclo(CFCV-MeGly-R*YCVCYRV)
(SEQ ID NO: 220);
cyclo(CYCRR*RFCVCVRWL)
(SEQ ID NO: 221);
cyclo(CYCRRRFCVCVRWL)
(SEQ ID NO: 222);
cyclo(CYCVRRYCVCYRWV)
(SEQ ID NO: 223);
cyclo(CYCKKKFCVCVL) (SEQ ID NO: 224);
cyclo(CYCKKKFCVCVWY) (SEQ ID NO: 225);
cyclo(CYCKKKFCVCVWL) (SEQ ID NO: 226);
cyclo(CYCKKKFCVCVKL) (SEQ ID NO: 227);
cyclo(CFCKPFCVCVK-Cha)
(SEQ ID NO: 228);
cyclo(CYCRRRFCVCVL) (SEQ ID NO: 229); and
cyclo(CYCRGRFCVCVGRGGWRL)
(SEQ ID NO: 230).
______________________________________
11. A cyclic peptide having antimicrobial activity against E. coli,
Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus or
vancomycin-resistant Enterococcus faecium and having the formula:
##STR13##
wherein m=0,1,2 and n=0,1 with the proviso that when m=2, n=0; X.sub.21,
X.sub.22, X.sub.24, X.sub.25, X.sub.27 and X.sub.28 are each independently
present or absent;
X.sub.7 and X.sub.14 are either both present or both absent;
X.sub.8 and X.sub.13 are either both present or both absent;
X.sub.2, X.sub.3, X.sub.4, X.sub.5, X.sub.7, X.sub.8, X.sub.13, X.sub.14,
X.sub.16, X.sub.17, X.sub.18, X.sub.19, X.sub.21,
X.sub.22, X.sub.27 and X.sub.28 are each independently a hydrophobic amino
acid, a hydrophilic amino acid or a small amino acid, with the provisos
that (i) when X.sub.2 is a hydrophobic amino acid X.sub.7, X.sub.14,
X.sub.19, X.sub.21 and X.sub.28 are each independently a hydrophobic amino
acid or a small amino acid and X.sub.3, X.sub.8, X.sub.13, X.sub.18,
X.sub.22 and X.sub.27 are each independently a hydrophilic amino acid or a
small amino acid; and (ii) when X.sub.2 is a hydrophilic amino acid
X.sub.7, X.sub.14, X.sub.19, X.sub.21 and X.sub.28 are each independently
a hydrophilic amino acid or a small amino acid and X.sub.3, X.sub.8,
X.sub.13, X.sub.18, X.sub.22 and X.sub.27 are each independently a
hydrophobic amino acid or a small amino acid;
X.sub.23, X.sub.24, X.sub.25 and X.sub.26 taken together are a peptide
loop;
Z.sub.1, Z.sub.6, Z.sub.15 and Z.sub.20 are each independently a
hydrophilic amino acid, a small amino acid or a cysteine-like amino acid;
X.sub.9, X.sub.10, X.sub.11, and X.sub.12 taken together are a peptide
.beta.-turn;
at least one of X.sub.9, X.sub.10, X.sub.11, X.sub.12, X.sub.23, X.sub.24,
X.sub.25 or X.sub.26 is a basic amino acid; and
wherein the peptide has a net positive charge at physiological pH.
12. A cyclic peptide having antimicrobial activity against E. coli,
Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus or
vancomycin-resistant Entereococcus faecium comprising:
an amphiphilic anti-parallel .beta.-sheet composed of first and second
anti-parallel strands, each strand containing 3 to 11 amino acid residues
and having an N-terminus and a C-terminus;
a first means for covalently linking the N-terminus of the first strand to
the C-terminus of the second strand; and
a second means for covalently linking the C-terminus of the first strand to
the N-terminus of the second strand.
13. The cyclic peptide of claim 12, wherein said first means is a loop and
said second means is a .beta.-turn.
14. The cyclic peptide of claim 13, wherein said loop is a peptide loop and
said .beta.-turn is a peptide .beta.-turn.
15. A composition comprising a cyclic peptide according to claim 1 in
admixture with a carrier or excipient.
16. A method of inhibiting the growth of a microbe, the method comprising
the step of contacting a microbe with an antimicrobially effective amount
of a cyclic peptide according to claim 1.
17. A method of treating a microbial infection, the method comprising the
step of administering to a subject in need thereof an effective amount of
a compound according to claim 1.
18. The method of claim 17, wherein the infection is caused by
vancomycin-resistant Enterococcus faecium, methicillin-resistant
Staphylococcus aureus, penicillin-resistant Streptococcus pneumoniae or
Pseudomonas aeruginosa. |
|
 |
|
 |
Claims |
|
|
|
Description |
|
|
1. FIELD OF THE INVENTION
The present invention is directed to cyclic peptides having broad spectrum
antimicrobial activity. The cyclic peptides are biocidal against a wide
variety of pathogens, including clinically relevant vancomycin resistant
Enterococcus faecium, methicillin resistant Staphylococcus aureus and
penicillin-resistant Streptococcus pneumoniae. The cyclic peptides of the
invention have improved efficacy, bioavailability and/or serum half-life
as compared to non-cyclized analogues.
2. BACKGROUND OF THE INVENTION
With the recent dramatic rise of antibiotic-resistant pathogens and
infectious diseases, the need for new antimicrobial agents is urgent
(Cohen et al., 1992, Science 257:1050-1055). For example, recently strains
of Enterococcus faecium that are resistant to vancomycin have been
observed (Moellering, 1990, Clin. Microbiol. Rev. 3:46-65). As vancomycin
is considered to be the antibiotic of last resort for several pathogens,
strains resistant to vancomycin pose a serious health threat to society.
Despite this urgency, in more than ten years only one completely different
type of antibiotic, a streptogramin mixture called Synercid (Rhone-Poulenc
Rorer, Collegeville, Pa.), has reached Phase III clinical trials
(Pfeiffer, 1996, "New Anti-Microbial Therapies Described," Genetic
Engineering News 16(8):1).
Recently, a new class of antimicrobial or antibiotic agents based on
naturally-occurring antimicrobial peptides produced within plants, animals
and insects have been discovered. These peptides include, among others,
cecropins (Hultmark et al., 1980, Eur. J. Biochem. 106:7-16; Hultmark et
al., 1982, Eur. J. Biochem. 127:207-217), apidaecins (Casteels et al.,
1989, EMBO J. 8:2387-2391), magainins (Zasloff, 1987, Proc. Natl. Acad.
Sci. U.S.A. 84:5449-5453; Zasloff et al., 1988, Proc. Natl. Acad. Sci.
U.S.A. 85:910-913), tachyplesins and analogues of tachyplesins such as
polyphemusins (Nakamura et al., 1988, J. Biol. Chem. 263:16709-16713;
Miyata et al., 1989, J. Biochem. 106:663-668), defensins (Lehrer et al.,
1991, Cell 64:229-230; Lehrer et al., 1993, Ann. Rev. Immunol. 11:105-128;
U.S. Pat. No. 4,705,777; U.S. Pat. No. 4,659,692; U.S. Pat. No.
4,543,252), .beta.-defensins (Selsted et al., 1993, J. Biol. Chem.
288:6641-6648; Diamond et al., 1991, Proc. Natl. Acad. Sci. U.S.A.
88:3952-3958), insect defensins (Lambert et al., 1989, Proc. Natl. Acad.
Sci. U.S.A. 88:262-265; Matsuyama and Natori, 1988, J. Biol. Chem.
263:17112-17116), and protegrins (Kokryakov et al., 1993, FEBS
337:231-236; Zhao et al., 1994, FEBS Letters 346:285-288; Migorodskaya et
al., 1993, FEBS 330:339-342; Storici et al., 1993, Biochem. Biophys. Res.
Co | | |
