KLUYVEROMYCES-MARXIANUS CDBB-L-278 - A WILD INULINASE HYPERPRODUCING STRAIN

Kluyveromyces marxianus CDBB-L-278 is an inulinase hyperproducing stra in. It was able to grow in a medium containing inulin as the unique ca rbon source in the presence of 2-deoxyglucose. It produced up to 3.3 t imes the activity of the control strain K. marxianus NCYC-1429 in an i nulin medium, and 3.6 times in a medium with glycerol as the sole carb on source. Although the strain CDBB-L-278 was able to produce inulinas e in the presence of 2-deoxyglucose, it was demonstrated that it is no t a de-repressed strain since enzyme production was reduced when the c oncentration of glucose or fructose was increased in the medium. Since inulinase was produced in a glycerol medium without an inducer, it ca n be considered that the enzyme production was partially constitutive in K. marxianus CDBB-L-278 as well as strain NCYC-1429. The inulinase from K. marxianus CDBB-L-278 was characterized. It had a higher affini ty for inulin than for sucrose. Temperature and pH profiles were diffe rent for both of these two substrates. The enzyme was stable to high t emperatures, with a half-life of 180 min at 50 degrees C.