Table 1.

Genes encoding proteins with known or putative PG lytic domains and WalRK_Spn-regulated genes in S. pneumoniae serotype 2 strain D39

Gene or tag	Hydrolase classa	Domain nameb	Cell morphology due to deletion mutatione	Relative growth of deletion mutante	Relative PG peptide profile of deletion mutante	Reference(s)
WalRKSpn regulon
pcsB	Putative N-acetylmuramoyl-l-alanine amidase/endopeptidase	CHAP	Essential	None	WTc upon depletion	1, 42
lytB	N-Acetylglucosaminidase	Glucosaminidase	WT with slightly longer chains, very long chains when capsule is absent	WT	NDd	This work, 7, 15
spd_1874 (spr1875)	Putative N-acetylmuramidase	Mt3 hydrolytic	WT	WT growth rate and yield, slight lag when capsule is absent	WT	This work
spd_0703 (spr0709)	None (putative SEDS protein)	None	WT with aberrant incorporation of PG peptides	WT	WT	This work
spd_0104 (spr0096)	None (LysM domain)	None	WT	WT	ND	This work
Cell division
pmp23	Putative lytic transglycosylase	PECACE	Aberrant cell morphology, i.e., long cells or large rounded cells within or at ends of chains, cell asymmetry	WT growth rate, decreased yield	WT	This work, 45, 47
dacA	d,d-Carboxypeptidase	Peptidase S11	Aberrant cell morphology, i.e., rounded cells, asymmetry, septal defects exaggerated when capsule is absent	Decreased growth rate and yield, lag	Aberrant	This work, 1, 38, 59
dacB (spd_0549; spr0554)	l,d-Carboxypeptidase	VanY/MEROPS M15 peptidase	Aberrant cell morphology, i.e., asymmetry, long chains, no chaining when capsule is absent	WT growth rate and yield and slight lag, slight decrease in growth rate and yield and slight lag when capsule absent	Aberrant	This work
Fratricide and autolysis during growthd
lytA	N-Acetylmuramoyl-l-alanine amidase	Amidase_2	WT with infrequent cell asymmetry, slight chaining when capsule is absent	WT	ND	This work, 11, 18, 58
cbpD	Putative N-acetylmuramoyl-l-alanine amidase/endopeptidase	CHAP	WT	WT	WT	This work, 11, 12, 19, 26
lytC	N-Acetylmuramidase	Glyco_hydro_25	WT with slightly longer chains, slight chaining when capsule is absent	WT	WT	This work, 11, 20, 37, 48
Other putative hydrolases that do not affect cell division
spd_0873 (spr_0890)	Putative N-acetylmuramidase	Glyco_hydro_25	WT	WT	ND	This work
spd_0173 (spr_0168)	Putative l,d-carboxypeptidase	Peptidase S66	WT	WT	ND	This work

^aBased on reference 30.

^bDetermined using Pfam site (14).

^cWT, phenotype similar to that of parent strain.

^dND, not determined.

^eDeterminations of growth properties, cell morphologies, and PG peptide compositions of deletion mutants were performed as described in Materials and Methods. PG peptide compositions upon depletion of PcsB and in Δpmp23 mutants were reported previously in references 1 and 45, respectively.