Extended Data Table 2b. Time course adaptation experiments with synchronously replicating dnaC2 temperature sensitive cells.

Temperature sensitive K-12ΔcasCdnaC2 culture was transferred to 39°C for 70 minutes. Cas1+2 expression was then induced for 30 minutes using 0.2% L-arabinose and 0.1mM IPTG, and the culture was transferred to 30°C with continuous induction of Cas1+2. Culture was sampled at successive time points following synchronous replication initiation, and the CRISPR array was amplified and sequenced to determine the fraction of cells that acquired a new spacer. In addition, gel-separated expanded arrays were amplified and sequenced, to study the localization of spacers derived from the chromosome.

		Sequencing of the CRISPR array PCR product				Direct sequencing of expanded arrays
Sample	rep	# of reads spanning the CRISPR array	# of reads supporting unmodified parental array	# of reads supporting acquisition of a new spacer	% expanded arrays	# spacers from chromosome	# spacers from Ter region	% spacers from Ter
dnaC2 0 min, 30°	1	99,683	99,669	14	0.014%	3,684	508	13.79%
dnaC2 0 min, 30°	2	107,825	107,814	11	0.010%	456	26	5.70%
dnaC2 20 min, 30°	1	107,679	107,671	8	0.007%	1,250	128	10.24%
dnaC2 20 min, 30°	2	113,040	113,030	10	0.009%	1,402	36	2.57%
dnaC2 40 min, 30°	1	394,058	394,018	40	0.010%	4,830	930	19.25%
dnaC2 40 min, 30°	2	100,975	100,964	11	0.011%	10,541	2,821	26.76%
dnaC2 60 min, 30°	1	63,978	63,967	11	0.017%	5,563	1,604	28.83%
dnaC2 60 min, 30°	2	108,605	108,588	17	0.016%	6,551	2,183	33.32%
dnaC2 90 min, 30°	1	109,652	109,636	16	0.015%	3,221	348	10.80%
dnaC2 90 min, 30°	2	206,652	206,567	85	0.041%	2,827	320	11.32%
dnaC2 120 min, 30°	1	80,213	80,192	21	0.026%	3,373	848	25.14%
dnaC2 120 min, 30°	2	121,583	121,530	53	0.044%	3,135	721	23.00%