ENZIMOLOGI ENZIM KELAS 3 4.docx

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http://www.chem.qmul.ac.uk/iubmb/

KELAS : EC 3. HYDROLASES

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SUBKELAS SUB SUB KELAS ENZIM

SPESIFIK REAKSI KETERANGAN

3.1 Acting on

ester bonds 3.1.1 Carboxylic esterhydrolases EC3.1.1.polyneuridi7 ne-epivellosimine + methanol

Following hydrolysis of this indole alkaloid ester the carboxylic acid decarboxylates

spontaneously giving the sarpagan skeleton. The enzyme also acts on akuammidine aldehyde (the 16-epimer of polyneuridine aldehyde). 3.2 Glycosylases 3.2.1 Glycosidases, i.e.

enzymes

hydrolysing O- an d S-glycosyl compounds

EC 3.2.1.1

α-amylase Reaction: Pati + H2O  Dekstrin + Pati

Endohydrolysis of (1→4)-α-D-glucosidic linkages in polysaccharides containing three or more (1→4)-α-linked D-glucose units.

Acts on starch, glycogen

and related

polysaccharides and oligosaccharides in a random manner; reducing groups are liberated in the α-configuration. The term ‘α’ relates to the initial anomeric configuration of the free sugar group released and not to the configuration of the linkage hydrolysed.

3.3 Acting on ether bonds

3.3.2 Ether hydrolases EC3.3.2.1 isochorism atase

Isochorismate + H2O  (2S,3S)-2,3-Dihydro-2,3-dihydroxybenzoate + Pyruvate

The enzyme is involved in the biosynthesis of several siderophores, such as

2,3-3.4.11 Aminopeptidases EC3.4.11.1 leucyl aminopepti dase

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KELAS : EC 4. LYASES

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SUBKELAS SUB SUB KELAS ENZIM

SPESIFIK REAKSI KETERANGAN

4.1

Carbon-2-oxo carboxylate  an aldehyde + CO2 A thiamine-diphosphate protein. Also catalyses acyloin formation.

4.2 Carbon-Oxygen Lyases

4.2.1 Hydro-Lyases EC 4.2.1.1 carbonate

L-aspartate = fumarate + NH3

4.4

Carbon-L-methionine + H2O  methanethiol + NH3 + 2-oxobutanoate (overall reaction)

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