Rhodotorula glutinis and method for preparing (S)-hydroxy propionamide from rhodotorula glutinis

[0024] Example 1 Substrate synthesis

[0025]

[0026] Methyl 3-oxo-3-(2-thienyl)propionate N-methyl-3-oxo-3-(2-thienyl)propionamide

[0027] Preparation of 3-oxo-3-(2-thienyl) methyl propionate:

[0028] At room temperature, in a dry three-necked flask equipped with a condenser, a constant pressure dropping funnel, and mechanical stirring, add 500 ml of dry toluene, 0.2Mol NaH, and 0.11Mol dimethyl carbonate at room temperature, and heat the reaction device in an oil bath to Reflux and slowly drop in 0.1Mol thiophene ethyl ketone. At this time, a lot of bubbles are generated. After the dropping is completed, continue to heat and reflux. TCL detects that the raw material has reacted completely. Stop heating, cool the reaction mixture to room temperature, and slowly drop under an ice bath. Add 20ml methanol to extract the reaction, add dilute hydrochloric acid (1M) to the mixed solution to adjust the pH to neutral, extract, take the organic layer, continue to extract the aqueous phase w

[0031] Example 2 Screening of strains

[0032] Inoculate the preserved strains to be screened in liquid yeast culture medium under aseptic conditions (see the instructions for the medium components), culture at 30°C, 230 revolutions per minute, and shake culture for 24 hours to prepare seeds. Connect to fresh liquid yeast culture medium, at 30°C, 230 rpm, shaking culture for 40 hours. The cultured bacterial liquid was centrifuged at 8000 rpm for 5 minutes at 4°C, and the precipitated bacterial cells were collected and washed thoroughly with potassium phosphate buffer (0.1M, pH 7.0) to obtain wet bacterial cells as a biocatalyst.

[0033] The wet bacteria were prepared with the above buffer to form a bacterial suspension with a concentration of 80g / l, 1g / l N-methyl-3-oxo-3-(2-thienyl)propionamide was added, and 1% glucose was added And 5% isopropanol as coenzyme regeneration substrate, the biotransformation system is 10ml. Under the condition of 30°C, 230 revolutions per minute,

[0034] Example 3 Identification of screening strains

[0035] In order to determine the taxonomic status of the strain and understand its performance in detail, a preliminary identification of the strain was carried out. This strain has the following characteristics:

[0036] Morphological characteristics: spherical or ellipsoidal, red, moist, round, neat edges, and opaque in the lag phase.

[0037] Physiological and biochemical characteristics:

[0038] (1) Acid production test: positive;

[0039] (2) Ester production test: positive;

[0040] (3) Starch-like test: negative;

[0041] (4) Diazo Blue B (DBB) test: positive;

[0042] (5) Urease test; positive;

[0043] (6) Myricetin decomposition test: positive;

[0044] (7) Assimilation ethanol test: positive;

[0045] (8) Assimilation nitrogen source (KNO3) test: positive;

[0046] (9) Litmus milk reaction test: turn red;

[0047] (10) Carbon source assimilation test: positive: Glucose, sucrose, maltose, raffinose, melezitose, α-methyl-glucoside,