TABLE 3.

Murein hydrolases of E. coli

Hydrolase	Map position		Gene	Enzyme	Size (kDa)	Localization	Reference(s)
	kb	min
Lytic transglycosylase
	4628	99.7	sltY	Soluble lt 70 (Slt70)	70	Periplasm	42, 61
	2944	63.4	mltA	Membrane-bound lt A (MltA)	38	Outer membrane	101, 158
	2824	60.9	mltB	Membrane-bound lt B (MltB)	39	Outer membrane	41
				Soluble lt 35 (Slt35) (proteolytic product of MltB)	35	Periplasm	36, 43
	3102	66.9	mltC	Membrane-bound lt C (MltC)	40	Outer membrane	34
	1243	26.8	emtA	Endospecific membrane-bound ltA (endo-Mlt)	22	Outer membrane	94
β-N-Acetylglucosaminidase
	1163	25.1	nagZ	β-N-Acetylglucosaminidase	37	Cytoplasm	117, 145
N-Acetylmuramyl-l-alanine amidases
	2550	55.0	amiA	Muramyl-l-alanine amidase A	28	Periplasm	154
	4394	94.7	amiB	Muramyl-l-alanine amidase B	48	Periplasm	155
	2946	63.5	amiC	Muramyl-l-alanine amidase C	43	Periplasm	147
	119	2.6	ampD	N-Acetylanhydromuramyl-l-alanine amidase	20.5	Cytoplasm	72, 81
dd-Endopeptidases
	3326	71.7	dacB	PBP4 (additional d,d-carboxypeptidase IB activity)	48	Membrane associated	93, 106
	2232	48.1	pbpG	PBP7, PBP8 (proteolytic product of PBP7)	31	Membrane associated	63, 127, 157
	2444	52.7	mepA	MepA	28	Periplasm	84
dd-Carboxypeptidases
	663	14.3	dacA	d,d-Carboxypeptidase (PBP5)	40	Inner membrane	18
	880	19.0	dacC	d,d-Carboxypeptidase (PBP6)	40	Inner membrane	18
	2080	44.8	dacD	d,d-Carboxypeptidase (PBP6B)	43.5	Inner membrane	2