TABLE 1.

Description of spoIIR mutants

Allele	Amino acid change	Base change	Sporulation (% of parental spo+ strain BR151)	Mutagenc
spoIIRΔneo		Insertion at codon 111	<2.9 × 10−6
spoIIR11		Deletion of TA	1.4 × 10−1	NA
spoIIR29	Gln→ochre	CAA→TAA	4.0 × 10−3	MHA
spoIIR40	Gln→amber	CAG→TAG	7.7 × 10−3	MHA
spoIIR44	Arg→Cys	CGT→TGT	4.8 × 10−4	MHA
spoIIR74	Trp→opal	TGG→TGA	2.9 × 10−1	MHA
spoIIR144	Gly→opal	GGA→TGA	6.1 × 10−3	NA
spoIIR151	Trp→opal	TGG→TGA	2.3 × 10−4	MHA
spoIIR152 (spoIIR4a)	Trp→opal	TGG→TGA	6.7 × 10−3	EMS; MHAb
spoIIR153 (spoIIR3a)	Cys→Tyr	TGT→TAT	6.1 × 10−3	EMS; MHAb
spoIIR157L (spoIIR1a)	Pro→Leu	CCG→CTG	3.5 × 10−1	EMS
spoIIR157S (spoIIR2a)	Pro→Ser	CCG→TCG	7.0 × 10−1	EMS; MHAb

^aOriginal allele name (20). 

^bSame mutant allele was obtained by two different mutagenesis protocols (see text). 

^cNA, nitrous acid; MHA, methoxyamine.