. Author manuscript; available in PMC: 2010 Feb 20.

Published in final edited form as: J Mol Biol. 2009 Jan 3;386(2):300–315. doi: 10.1016/j.jmb.2008.12.064

Table 1.

L4 and L22 mutant selection statistics

Macrolide	Mutagenized codon^a	Colonies isolated	Survived 2° selection	Passed PCR screen	Clones sequenced	L4/L22 mutants^b
Erythromycin
	L4
	Gln62	136	117	98	96	69
	Lys63	130	121	110	98	96
	Gly64	159	149	117	96	96
	Thr65	129	121	89	89	65
	Gly66	170	167	99	96	56
	Arg67	246	172	81	81	76
	Gln62Phe	33	31	NP^c	31	20
	Gln62Lys	33	19	NP^c	19	0
	Thr65Pro	31	31	31	24	24
	Thr65Ser	46	37	29	24	21
	L22
	Arg88	201	82	49	48	33
	Ala89	167	117	100	96	45
	Lys90	98	98	96	96	96
	Gly91	79	79	12	6	4
	Arg92	135	94	61	48	30
	Ala93	81	81	53	53	13
Spiramycin
	L4
	Gln62	98	81	68	48	46
	Lys63	97	93	62	48	48
	Gly66	49	49	48	48	48
Tylosin
	L22
	Lys90	97	88	57	48	47

Individual codons were randomized using oligonucleotide libraries except where specific mutations are indicated.

Indicates that L4 or L22 mutations were identified within and/or adjacent to the target codon. Several erythromycin-resistant isolates contained wild-type L4 and L22, and presumably these cells contain unidentified macrolide-resistance mutations.

3′-mismatch PCR screening was not performed (NP) on mutants from these selections.