Manulis Shulamit, Shafrir Hadas, Epstein Ephraim, Lichter Amnon, Barash Isaac
Microbiology (Reading). 1994 May;140 ( Pt 5):1045-1050. doi: 10.1099/13500872-140-5-1045.
Various Streptomyces spp. including S. violaceus, S. scabies, S. griseus, S. exfoliatus, S. coelicolor and S. lividans secrete indole-3-acetic acid (IAA) when fed with L-tryptophan (Trp). Production of IAA was detected in Streptomyces strains causing potato scab as well as in non-pathogenic strains. The pathways for IAA synthesis from Trp were investigated in S. violaceus and S. exfoliatus. Indole-3-acetamide (IAM), indole-3-lactic acid (ILA), indole-3-ethanol (IEt) and IAA were identified by HPLC and GC-MS. Streptomyces cells were capable of catabolizing IAM, ILA, IEt and indole-3-acetaldehyde (IAAId) into IAA. Incorporation of radioactivity into IAM, IAA and ILA but not IEt was detected when cells were fed with L-[3-14C]tryptophan. Results indicate the presence of the IAM pathway (Trp-->IAM-->IAA) and the possible presence of additional pathways for IAA biosynthesis in Streptomyces.
包括紫色链霉菌、疮痂链霉菌、灰色链霉菌、脱落链霉菌、天蓝色链霉菌和变铅青链霉菌在内的多种链霉菌在以L-色氨酸（Trp）为食时会分泌吲哚-3-乙酸（IAA）。在引起马铃薯疮痂病的链霉菌菌株以及非致病菌株中均检测到了IAA的产生。在紫色链霉菌和脱落链霉菌中研究了从Trp合成IAA的途径。通过高效液相色谱法（HPLC）和气相色谱-质谱联用仪（GC-MS）鉴定出了吲哚-3-乙酰胺（IAM）、吲哚-3-乳酸（ILA）、吲哚-3-乙醇（IEt）和IAA。链霉菌细胞能够将IAM、ILA、IEt和吲哚-3-乙醛（IAAId）分解代谢为IAA。当用L-[3-14C]色氨酸喂养细胞时，检测到放射性掺入IAM、IAA和ILA中，但未掺入IEt中。结果表明链霉菌中存在IAM途径（Trp→IAM→IAA）以及IAA生物合成的其他可能途径。
