Glycoside Hydrolases Family 4; GlvA- and pagL-like glycosidases. Bacillus subtilis GlvA and Clostridium acetobutylicum pagL are 6-phospho-alpha-glucosidase, catalyzing the hydrolysis of alpha-glucopyranoside bonds to release glucose from oligosaccharides. The substrate specificities of other members of this subgroup are unknown. Some bacteria simultaneously translocate and phosphorylate disaccharides via the phosphoenolpyruvate-dependent phosphotransferase system (PEP_PTS). After translocation, these phospho-disaccharides may be hydrolyzed by the GH4 glycoside hydrolases, which include 6-phospho-beta-glucosidases, 6-phospho-alpha-glucosidases, alpha-glucosidases/alpha-glucuronidases (only from Thermotoga), and alpha-galactosidases. Members of this subfamily are part of the NAD(P)-binding Rossmann fold superfamily, which includes a wide variety of protein families including the NAD(P)-binding domains of alcohol dehydrogenases, tyrosine-dependent oxidoreductases, glyceraldehyde-3-phosphate dehydrogenases, formate/glycerate dehydrogenases, siroheme synthases, 6-phosphogluconate dehydrogenases, aminoacid dehydrogenases, repressor rex, and NAD-binding potassium channel domains, among others.

Alpha-galactosidase/6-phospho-beta-glucosidase, family 4 of glycosyl hydrolase [Carbohydrate transport and metabolism].

Glycoside Hydrases Family 4. Glycoside hydrolases cleave glycosidic bonds to release smaller sugars from oligo- or polysaccharides. Some bacteria simultaneously translocate and phosphorylate disaccharides via the phosphoenolpyruvate-dependent phosphotransferase system (PEP-PTS). After translocation, these phospho-disaccharides may be hydrolyzed by GH4 glycoside hydrolases. Other organisms (such as archaea and Thermotoga maritima) lack the PEP-PTS system, but have several enzymes normally associated with the PEP-PTS operon. GH4 family members include 6-phospho-beta-glucosidases, 6-phospho-alpha-glucosidases, alpha-glucosidases/alpha-glucuronidases (only from Thermotoga), and alpha-galactosidases. They require two cofactors, NAD+ and a divalent metal (Mn2+, Ni2+, Mg2+), for activity. Some also require reducing conditions. GH4 glycoside hydrolases are part of the NAD(P)-binding Rossmann fold superfamily, which includes a wide variety of protein families including the NAD(P)-binding domains of alcohol dehydrogenases, tyrosine-dependent oxidoreductases, glyceraldehyde-3-phosphate dehydrogenases, formate/glycerate dehydrogenases, siroheme synthases, 6-phosphogluconate dehydrogenases, aminoacid dehydrogenases, repressor rex, and NAD-binding potassium channel domains, among others.

Glycoside Hydrolases Family 4; Phospho-beta-glucosidase. Some bacteria simultaneously translocate and phosphorylate disaccharides via the phosphoenolpyruvate-dependent phosphotransferase system (PEP-PTS). After translocation, these phospho-disaccharides may be hydrolyzed by the GH4 glycoside hydrolases such as the phospho-beta-glucosidases. Other organisms (such as archaea and Thermotoga maritima ) lack the PEP-PTS system, but have several enzymes normally associated with the PEP-PTS operon. The 6-phospho-beta-glucosidase from Thermotoga maritima hydrolylzes cellobiose 6-phosphate (6P) into glucose-6P and glucose, in an NAD+ and Mn2+ dependent fashion. The Escherichia coli 6-phospho-beta-glucosidase (also called celF) hydrolyzes a variety of phospho-beta-glucosides including cellobiose-6P, salicin-6P, arbutin-6P, and gentobiose-6P. Phospho-beta-glucosidases are part of the NAD(P)-binding Rossmann fold superfamily, which includes a wide variety of protein families including the NAD(P)-binding domains of alcohol dehydrogenases, tyrosine-dependent oxidoreductases, glyceraldehyde-3-phosphate dehydrogenases, formate/glycerate dehydrogenases, siroheme synthases, 6-phosphogluconate dehydrogenases, aminoacid dehydrogenases, repressor rex, and NAD-binding potassium channel domains, among others.

Family 4 glycosyl hydrolase C-terminal domain.

2.1Angstrom Resolution Crystal Structure of 6-phospho-alpha-glucosidase from Gut Microorganisms in Complex with NAD and Mn2+ [Merdibacter massiliensis],6VC6_B 2.1 Angstrom Resolution Crystal Structure of 6-phospho-alpha-glucosidase from Gut Microorganisms in Complex with NAD and Mn2+ [Merdibacter massiliensis],6VC6_C 2.1 Angstrom Resolution Crystal Structure of 6-phospho-alpha-glucosidase from Gut Microorganisms in Complex with NAD and Mn2+ [Merdibacter massiliensis],6VC6_D 2.1 Angstrom Resolution Crystal Structure of 6-phospho-alpha-glucosidase from Gut Microorganisms in Complex with NAD and Mn2+ [Merdibacter massiliensis]

CrystalStructure Of Glva From Bacillus Subtilis, A Metal-requiring, Nad-dependent 6-phospho-alpha-glucosidase [Bacillus subtilis]

ChainA, 6-phospho-alpha-glucosidase [Klebsiella pneumoniae],6DUX_B Chain B, 6-phospho-alpha-glucosidase [Klebsiella pneumoniae],6DVV_A Chain A, 6-phospho-alpha-glucosidase [Klebsiella pneumoniae],6DVV_B Chain B, 6-phospho-alpha-glucosidase [Klebsiella pneumoniae]

Crystalstructure of Gan4C, a GH4 6-phospho-glucosidase from Geobacillus stearothermophilus [Geobacillus stearothermophilus],5C3M_B Crystal structure of Gan4C, a GH4 6-phospho-glucosidase from Geobacillus stearothermophilus [Geobacillus stearothermophilus],5C3M_C Crystal structure of Gan4C, a GH4 6-phospho-glucosidase from Geobacillus stearothermophilus [Geobacillus stearothermophilus],5C3M_D Crystal structure of Gan4C, a GH4 6-phospho-glucosidase from Geobacillus stearothermophilus [Geobacillus stearothermophilus]

2.3Acrystal structure of phospho-beta-glucosidase [Geobacillus stearothermophilus]

Maltose-6'-phosphate glucosidase OS=Fusobacterium mortiferum OX=850 GN=malH PE=1 SV=1

Maltose-6'-phosphate glucosidase MalH OS=Clostridium acetobutylicum (strain ATCC 824 / DSM 792 / JCM 1419 / LMG 5710 / VKM B-1787) OX=272562 GN=malH PE=1 SV=1

6-phospho-alpha-glucosidase OS=Leptotrichia buccalis (strain ATCC 14201 / DSM 1135 / JCM 12969 / NCTC 10249 / C-1013-b) OX=523794 GN=pagL PE=1 SV=1

Maltose-6'-phosphate glucosidase OS=Bacillus subtilis (strain 168) OX=224308 GN=glvA PE=1 SV=1

6-phospho-alpha-glucosidase OS=Klebsiella pneumoniae OX=573 GN=aglB PE=1 SV=1