Cryptococcus laurentii

This process uses cell suspensions of Cryptococcus laurentii which possess high L-df-amino- -caprolactamase activity, together v/i h Achromobacter oboe cells with high df-amino-df-caprolactam activity. 

Source of Enzyme (s) E. coli B. brevis and Agrobacterium radiobacter B. cereus, Candida bodinii Cryptococcus laurentii and Achromobacter obae P. putid,... 

The first of these enzymes has been studied the most thoroughly. Its activity has been detected in many sources, and purified preparations have been obtained from calf and beef liver,348-349 rat tissues,3498 hen oviduct,350 pea seedlings,351 Cryptococcus laurentii,352 and Aerobacter aerogenes,353 Extensive purification of the liver enzyme was achieved.349... 

Sugita T, Takashima M, Ideka R, Nakase T, Shinoda T Intraspecies diversity of Cryptococcus laurentii as revealed by sequences of internal transcribed spacer regions and 28S rDNA gene and taxonomic positions of C. laurentii clinical isolates. J Clin Microbiol 2000 38 1468-1471. 

Kooiman separated exocellular amylose formed in liquid media at pH < 5 by Cryptococcus albidus and Cryptococcus laurentii var. flavescens NRRL Y-1401 from a polysaccharide containing D-man-nose, D-xylose, and D-glucuronic acid. X-Ray diffraction patterns of the retrograded amyloses were identical with that of tuber starch (B modification). Periodate oxidation, optical rotational measurements, and hypoiodite oxidation data suggested a linear a-D-(l—>4)-linked structure having a chain length of about 44 units for the Cr. albidus amylose. Cryptococcus neoformans produces a crystalline amylose that was isolated by the method of Schoch. It has an iodine value and alpha- and hefa-amylase hydrolysis characteristics similar to those of corn amylose. 

For some years Foray s enzymatic process for L-lysine (L-Lys, 41) was competitive compared with fermentation. This chemoenzymatic L-Lys production was established with a capacity of 5000-10000 t/y. The key intermediate is a-amino-e-caprolactam (ACL), produced from cyclohexanone in a modified Beckmann rearrangement. The enantiospecific hydrolysis forming L-Lys is based on two enzymes L-ACL-hydrolase opens the ring of ACL to L-Lys and in the presence of the ACL-racemase the d-ACL is racemized. Incubating d,l-ACL with cells of Cryptococcus laurentii having l-ACL lactamase activity together with cells of Achromobacter obae with ACL-racemase activity, L-Lys could be obtained in a yield of nearly 100% (Scheme 24) [102]. 

The following organisms were used Cryptococcus laurentii, a yeast Aspergillus fumigatus gp. (Aspergillus fischeri), an enrichment culture isolate and a Fusarium sp. isolated in the laboratory. The fungi were stored as spore suspensions washed from Sabouraud s Dextrose Agar (Difco Detroit, Ml) with 0.1%... 

E1= L-aminolactam-hydrolase, whole cells from Cryptococcus laurentii E2= amino-lactam-racemase, whole cells from Achromobacter obae... 

L-Lysine, an essential amino acid, is used in very large quantities to supplement human foods and animal feeds. Traditionally, L-Lysine is produced by fermentation processes. An alternative route developed by Toray Ind. involves the chemical synthesis of D/L-a-amino-s-caprolactam followed by the selective hydrolysis of the L-a-amino-s-caprolactam catalyzed by intracellular lactamase in Cryptococcus laurentii, to give L-Lysine. The process can be improved by adding a second micro-organism, Achromobacter obae, containing a-amino-E-caprolactam racemase.Thus, quantitative yields of L-lysine are obtained. 

A nonfermentative yeast. Cryptococcus laurentii, produces a capsular polysaccharide that contains D-mannose, D-xylose, and D-glucuronic acid residues in the approximate molar ratios of 5 2 1. Structural studies indicate that the polysaccharide has a backbone of D-mannose residues, with D-xylose and D-glucuronic acid residues as end groups. A particulate fraction from this organism was shown to catalyze the transfer of the D-xylosyl group from its UDP derivative to acceptor polysaccharides. The transferase can be solubilized with digitonin. Partially de-D-xylosylated capsular polysaccharide from the parent strain is most active as the acceptor, and similarly treated polysaccharides from related species are active to a lesser degree. Neither untreated capsular polysaccharides from these strains nor S. cerevisiae mannan showed any activity as an acceptor. 

Furanocoumarins also have photosensitizing effect on dermatophytes [132]. Xanthotoxin (36) showed activity in darkness against Candida albicans and Cryptococcus laurentii [133]. 

Cell extracts of Cryptococcus laurentii, a yeast which synthesizes amylose when grown at low pH, contain an a-D-glucan phosphorylase (EC 2.4.1.1) which has been characterized. Evidence for a possible role of this enzyme in the biosynthesis of amylose was reported. 

T., Nakase, T. (2003). Three new combinations from the Cryptococcus laurentii complex Cryptococcus aureus, Cryptococcus carnescens and Cryptococcus peneaus. International Journal of Systematic and Evolutionary Microbiology 53,1187-1194. 

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