Table 3.

Phage strains

Notation	Genotype	Use	Ref
T7+	Wild-type (Genbank V01146)	Control phage for some adaptations	[20]
T7v	T7 cloning vector, made as T7Select 415b-1 (Novagen) with the left end BclI fragment replaced by that of a phage carrying the C74 deletion (gene 0.3 is intact)	Used as backbone for gene insertions because of the cloning site and the ability to grow on hosts containing type I restriction modification (RM)	T7 0 in [15]
T7dsp+trx 10B	T7415-C74:trxAdspB. T7v with the E. coli trxA gene, T7 ϕ10 promoter and A. actinomycetemcomitans CU1000 dspB gene recombined in to the multiple cloning site between genes 10 and 11	Re-engineered version of T7DspB from [4] to grow on hosts with type I RM	This study
T7dsp+trx 10B / dsp 10B	T7dsp+trx 10B grown on a host with pUC57-T7dspB to remove the trxA gene by recombination; not clonally isolated	Used to allow evolution of dispersin free of trxA	This study
T7dsp+1.2 3.8	T7v but most of gene 3.8 replaced with T3 gene 1.2 (enabling growth on F plasmid-bearing strains) and the dspB gene. Created by recombination with plasmid pMK-RQ-T7trxAdspB. The multiple cloning site in gene 10B is unaltered from T7v.	Used to create T7-1.2+dsp 3.8/dsp 3.8.	This study
T7dsp+1.2 3.8/ dsp 3.8	T7-1.2+dsp 3.8 recombined with pMKRQ-T7dspB to create variation in the presence/absence of the 1.2 gene. Not purified.	Evolved in a chemostat to study evolution of the dsp gene.	This study
T7dsp 3.8P	The initial mix of T7-1.2+dsp 3.8/dsp 3.8 recombined against the chemostat-evolved population of T7-1.2+dsp 3.8/dsp 3.8 in which the dsp gene had been lost.	Multiple recombinations separated dsp from 1.2 and introduced any mutations from a chemostat adaptation that might be beneficial in the background of the phage. This polymorphic population was used to evaluate the effect of selection on the dsp transgene in serial transfer, short term biofilms and long term biofilms.	This study