Characterization of inulolytic enzymes from the Jerusalem artichoke-derived Glutamicibacter mishrai NJAU-1

Lian D., Zhuang S., Shui C., Zheng S., Ma Y., Sun Z., ...Daha Fazla

APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, cilt.106, sa.17, ss.5525-5538, 2022 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 106 Sayı: 17
  • Basım Tarihi: 2022
  • Doi Numarası: 10.1007/s00253-022-12088-6
  • Dergi Adı: APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, ABI/INFORM, Applied Science & Technology Source, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chemical Abstracts Core, Compendex, Computer & Applied Sciences, EMBASE, Environment Index, Food Science & Technology Abstracts, Geobase, MEDLINE, Pollution Abstracts, Veterinary Science Database
  • Sayfa Sayıları: ss.5525-5538
  • Anahtar Kelimeler: Bio fructose, Exo-inulinase, Glutamicibacter mishrai, Fructan, Jerusalem artichoke, TOLERANT EXO-INULINASE, MICROBIAL INULINASES, EXTRACELLULAR EXOINULINASE, PURIFICATION, CLONING, EXPRESSION, ARTHROBACTER, HYDROLYSIS, FRUCTOSE, CHICORY
  • Marmara Üniversitesi Adresli: Evet

Özet

The rhizosphere context of inulin-accumulating plants, such as Jerusalem artichoke (Helianthus tuberosus), is an ideal starting basis for the discovery of inulolytic enzymes with potential for bio fructose production. We isolated a Glutamicibacter mishrai NJAU-1 strain from this context, showing exo-inulinase activity, releasing fructose from fructans. The growth conditions (pH 9.0; 15 degrees C) were adjusted, and the production of inulinase by Glutamicibacter mishrai NJAU-1 increased by 90% (0.32 U/mL). Intriguingly, both levan and inulin, but not fructose and sucrose, induced the production of exo-inulinase activity. Two exo-inulinase genes (inu/ and inu2) were cloned and heterologously expressed in Pichia pastoris. While INU2 preferentially hydrolyzed longer inulins, the smallest fructan 1-kestose appeared as the preferred substrate for INU1, also efficiently degrading nystose and sucrose. Active site docking studies with GFn- and Fn-type small inulins (G is glucose, F is fructose, and n is the number of beta (2-1) bound fructose moieties) revealed subtle substrate differences between INU1 and INU2. A possible explanation about substrate specificity and INU's protein structure is then suggested.