Biomaterial Database

Location of the essential cysteine residue of jack bean urease. 1987

K Takishima, and G Mamiya

Department of Biochemistry, National Defense Medical College, Saitama, Japan.

Jack bean urease is inactivated by the modification of about one cysteine residue per subunit with N-ethylmaleimide (NEM) or other thiol titrant. The location of this cysteine residue was identified. After blocking the unessential thiol groups with NEM, the essential cysteine was labeled with N-(4-dimethylamino-3,5-dinitrophenyl)maleimide (DDPM). The DDPM-labeled protein was cleaved with cyanogen bromide and a DDPM-fragment was purified by gel filtration and ion exchange chromatography. Amino-terminal amino acid sequence of the DDPM-labeled fragment corresponded to that of a cyanogen bromide fragment of urease, VCHHLDREIPEDLAFAHSRIRKKTIAAEDVLNDIGAISIISSDSQAM. The second residue, Cys-592 in native urease, was labeled with DDPM. Fluoride ion, which competitively inhibits urease activity, protected urease from inactivation by NEM. The dissociation constant of fluoride ion obtained from the rate of inactivation with NEM was essentially identical to both the kinetically and spectrophotometrically determined dissociation constants. These suggest that the essential cysteine is at or near the active site.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D007887	Fabaceae	The large family of plants characterized by pods. Some are edible and some cause LATHYRISM or FAVISM and other forms of poisoning. Other species yield useful materials like gums from ACACIA and various LECTINS like PHYTOHEMAGGLUTININS from PHASEOLUS. Many of them harbor NITROGEN FIXATION bacteria on their roots. Many but not all species of "beans" belong to this family.	Afzelia,Amorpha,Andira,Baptisia,Callerya,Ceratonia,Clathrotropis,Colophospermum,Copaifera,Delonix,Euchresta,Guibourtia,Legumes,Machaerium,Pithecolobium,Stryphnodendron,Leguminosae,Pea Family,Pithecellobium,Tachigalia,Families, Pea,Family, Pea,Legume,Pea Families
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D010446	Peptide Fragments	Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.	Peptide Fragment,Fragment, Peptide,Fragments, Peptide
D010944	Plants	Multicellular, eukaryotic life forms of kingdom Plantae. Plants acquired chloroplasts by direct endosymbiosis of CYANOBACTERIA. They are characterized by a mainly photosynthetic mode of nutrition; essentially unlimited growth at localized regions of cell divisions (MERISTEMS); cellulose within cells providing rigidity; the absence of organs of locomotion; absence of nervous and sensory systems; and an alternation of haploid and diploid generations. It is a non-taxonomical term most often referring to LAND PLANTS. In broad sense it includes RHODOPHYTA and GLAUCOPHYTA along with VIRIDIPLANTAE.	Plant
D010946	Plants, Medicinal	Plants whose roots, leaves, seeds, bark, or other constituent parts possess therapeutic, tonic, purgative, curative or other pharmacologic attributes, when administered to man or animals.	Herbs, Medicinal,Medicinal Herbs,Healing Plants,Medicinal Plants,Pharmaceutical Plants,Healing Plant,Herb, Medicinal,Medicinal Herb,Medicinal Plant,Pharmaceutical Plant,Plant, Healing,Plant, Medicinal,Plant, Pharmaceutical,Plants, Healing,Plants, Pharmaceutical
D001726	Bisacodyl	A diphenylmethane stimulant laxative used for the treatment of CONSTIPATION and for bowel evacuation. (From Martindale, The Extra Pharmacopoeia, 30th ed, p871)	Agaroletten,Apo-Bisacodyl,Bekunis Bisacodyl,Bicol,Bisac-Evac,Bisacodyl Tannex,Bisacodyl Uniserts,Bisalax,Bisco-Lax,Bisco-Zitron,Dulco-Lax,Dulco-lax perles,Dulcolax,Durolax,Fleet Bisacodyl,Florisan N,Laxagetten,Laxanin,Laxans-ratiopharm,Laxbene,Laxysat Bürger,Lünolax,Rytmil,Ulcolax,ratio-Bisacodyl,Apo Bisacodyl,Bisac Evac,Bisacodyl, Bekunis,Bisacodyl, Fleet,Bisco Lax,Bisco Zitron,Dulco Lax,Dulco lax perles,Dulcolax perles,Laxans ratiopharm,Tannex, Bisacodyl,Uniserts, Bisacodyl,ratio Bisacodyl
D003545	Cysteine	A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.	Cysteine Hydrochloride,Half-Cystine,L-Cysteine,Zinc Cysteinate,Half Cystine,L Cysteine
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D014510	Urease	An enzyme that catalyzes the conversion of urea and water to carbon dioxide and ammonia. EC 3.5.1.5.	Phytourease,Urea Amidohydrolase,Amidohydrolase, Urea