Table 1 Strains and plasmids used in this study.

Bacterial strains

   S. ansochromogenes

7100

Wild-type strain

[31]

DNik

S. ansochromogenes 7100 containing plasmid pNIK

This work

E. coli

   DH5α

F-recA, f80, dlacZ ΔM15

Gibco BRL

   ET12567 (pUZ8002)

recE, dam, dcm, hsdS, Cm, Str, Tet, Km

[32]

   XL 1-blue MR

Δ(mcrA)183,Δ(mcrCB-hsdSMR-mrr)173, endA1, supE44, thi-1, recA1, gyrA96, relA1, lac

Stratagene

   BW25113

K12 derivative: ΔaraBAD, ΔrhaBAD

[33]

Plasmids

   pBluescript KS-

Routine cloning and subcloning vector

Stratagene

   pBS

Digestion of pBluescript II KS- with BamH I-Pst I, blunt-ended and religation.

This work

   supercos 1

Vector for cosmid library construction

Stratagene

   pSET152

Integrative vector

[22]

   pIJ790

λRED (gam, bet, exo), cat, araC, rep101^ts

[33]

   cosG4

A cosmid containing most of the nikkomycin biosynthetic genes

This work

   pLXP

11 kb DNA fragment containing partial nikkomycin biosynthetic genes inserted into pSET152

[18]

   pNIK

A pSET152 based plasmid containing the whole nikkomycin biosynthetic gene cluster

This work