1227. Biocytin

Nomenclature

CAS number: 576-19-2
N6-[5-(Hexahydro-2-oxo-1H-thieno[3,4-d]imidazol-4-yl)-1-oxopentyl]-l-lysine; ε-N-biotinyl-l-lysine; biotin complex of yeast.
C16H28N4O4S; mol wt 372.48.
C 51.59%, H 7.58%, N 15.04%, O 17.18%, S 8.61%.

Description and references

A naturally occurring complex of biotin. Contains 65.6% biotin. Isoln: Wright et al., J. Am. Chem. Soc. 72, 1048 (1950); 74, 1996 (1952). Structure: Peck et al., ibid. 72, 1048 (1950); 74, 1999 (1952). Synthesis: Wolf et al., ibid. 74, 2002 (1952); Weijlard et al., ibid. 76, 2505 (1954); Wolf, Folkers, US 2710298 (1955 to Merck & Co.). Purification: McCormick, F"ory, Methods Enzymol. 18 (pt A), 413 (1970). Review: A. F. Wagner, K. Folkers, Vitamins and Coenzymes (Wiley, New York, 1964) pp 138-159.

Chemical structure

Properties

Crystals, mp 241-243°. Upon rapid crystn from dil methanol or dil acetone, mp 228-230° (dec); upon slow crystn sinters at 227°. mp 245-252° (dec, microblock). Crystals from water, mp 228.5°. [α]D25 +53° (c = 1.05 in 0.1N NaOH). Infrared absorption spectrum: J. Am. Chem. Soc. 74, 2001 (1952). Freely sol in water, glacial acetic acid. Less sol in alc. Practically insol in acetone and most other organic solvents. When subjected to strong acid hydrolysis (at least 3N at 120° for one hour) biocytin yields biotin and l-lysine. Forms a crystalline hydrochloride. Biocytin is characterized microbiologically by its availability as a source of biotin to Lactobacillus casei, L. delbrückii LD 5, L. acidophilus, Streptococcus fecalis R, Neurospora crassa, and Saccharomyces carlsbergensis and by its unavailability as a source of biotin to Lactobacillus arabinosus, L. pentosus, and Leuconostoc mesenteroides P-60.