Mechanism	Inverting e
Clan	GH-M
3D Structure Status	( α / α ) 6 barrel
Catalytic Nucleophile/Base	Not known
Catalytic Proton Donor	Glu
Note	formerly known as cellulase family L. Some cellobiohydrolases of this family have been reported to act from the reducing ends of cellulose (EC 3.2.1.-), while others have been reported to operate from the non-reducing ends to liberate cellobiose or cellotriose or cellotetraose (EC 3.2.1.-). This family also contains endo-processive cellulases (EC 3.2.1.-), whose activity is hard to distinguish from that of cellobiohydrolases.
External resources	CAZypedia;
Statistics	GenBank accession (2116); Uniprot accession (29); PDB accession (31); 3D entries (12); cryst (0)

Bacteria
Protein Name	EC#	Organism	GenBank	Uniprot	PDB/3D Carbohydrate Ligands Resolution (Å)
ORF		Acetivibrio thermocellus			8ZU1[A] 2.84
exo-β-1,4-glucanase 48S (CelS; Clo1313_2747) (Cel48S)	3.2.1.176	Acetivibrio thermocellus DSM 1313	ADU75731.1 ACT46162.1	C7ED31	5YJ6[A] 1.43
cellobiohydrolase (CelS) (Cel48A)	3.2.1.176	Acetivibrio thermocellus F7	AAA23226.1	A3DH67 P0C2S5 P38686	1L1Y[A,B,C,D,E,F] β-D-Glcp-(1-4)-D-1-deoxy-Glcp 2.40 1L2A[A,B,C,D,E,F] β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp β-D-Glcp-(1-4)-D-1-deoxy-Glcp 2.50
multifunctional glycoside hydrolase (Cdan_2053; SOJ16_001858)	3.2.1.176	Anaerocellum danielii	WP_045175321.1 WPX08008.1	A0ABZ0U049	6D5D[A] β-D-Glcp-(1-4)-β-D-Glcp 1.90
cellulase 48B (CelB; BlCel48B; BLi01881; BL01231) (Cel48B)	3.2.1.4	Bacillus licheniformis DSM 13 = ATCC 14580	AAU40776.1 AAU23416.1 ACP61485.1	Q65JI8	7KW6[A] β-D-Glcp-(1-4)-β-D-Glcp β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp 1.68
BPUM_1559 (CelB)		Bacillus pumilus SAFR-032	ABV62241.1		5BV9[A] β-D-Glcp-(1-4)-β-D-Glcp 1.93 5CVY[A] β-D-Glcp-(1-4)-β-D-Glcp β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp L-2,3,4-deoxy-Xylp 2.00
UP12_08095		Bacillus pumilus SH-B9	AMM97308.1		5VMA[A] β-D-Glcp-(1-1)-<non_carb> β-D-Glcp-(1-4)-β-D-Glcp-(1-1)-<non_carb> 1.95
cellulase (CelA; CbCelA; Athe_1867; Cbes1867; Cbes_1867; CbCBH48A) (Cel9A+Cbh48A)	3.2.1.176	Caldicellulosiruptor bescii DSM 6725	ACM60955.1 CAB06786.1	B9MKU7 P96311	4EL8[A] 2.45 4L0G[A] β-D-Glcp-(1-4)-β-D-Glcp 2.00 4L0H[A] β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-α-D-Glcp 2.00 4L6X[A] 1.70 4TXT[A] β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp 2.00
exoglucanase S (ExgS;P70)	3.2.1.176	Clostridium cellulovorans ATCC 35296	AAC38571.3 AAC38571.2	O65986	4KIH[A] 2.05 4KKF[A] β-D-Glcp-(1-4)-α-D-Glcp β-D-Glcp-(1-4)-β-D-Glcp 1.70 4KKK[A] β-D-Glcp-(1-4)-β-D-Glcp β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp 2.88 4XWL[A] 2.05 4XWM[A] β-D-Glcp-(1-4)-α-D-Glcp β-D-Glcp-(1-4)-β-D-Glcp 1.70 4XWN[A] β-D-Glcp-(1-4)-β-D-Glcp β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp 2.88
cellulase (HCH_02465)	3.2.1.4	Hahella chejuensis KCTC 2396	ABC29272.1	Q2SJA2	4FUS[A] β-D-Glcp-(1-4)-β-D-Glcp 1.75
processive endo-cellulase F (CelF;Ccel_0729) (Cel48F)	3.2.1.176	Ruminiclostridium cellulolyticum H10	ACL75108.1 AAA73866.1 AAB41452.1	P37698	1F9D[A] β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp 2.30 1F9O[A] β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp1SH 2.50 1FAE[A] β-D-Glcp-(1-4)-β-D-Glcp 2.00 1FBO[A] β-D-Glcp-(1-1)-<non_carb> 2.30 1FBW[A] β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp 2.00 1FCE[A] β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp4S-(1-4)-β-D-Glcp-(1-1)-methyl 2.00 1G9G[A] 1.90 1G9J[A] β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp 1.90 2QNO[A] β-D-Glcp4S-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp4S-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp4S-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp4S-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp4S 2.00
β-1,4-exocellulase (E6; CelF; TfCel48A; Tfu_1959) (Cel48A)	3.2.1.176	Thermobifida fusca YX	AAD39947.1 AAZ55992.1 ACH05304.1	Q47NH7 Q9XCD4	4JJJ[A] β-D-Glcp-(1-4)-β-D-Glcp β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp-(1-4)-β-D-Glcp 1.60
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