TABLE 2.

Candidate chlamydial T3SS chaperone proteins

Annotation by strain or species				Common gene namee	Class	Associated operon/gene clustera	Expression during the developmental cycleb	Orthologs with homology to chlamydial chaperone proteinsc
D/UW-3CX	L2/434/Bu	C. pneumoniae	GPICd
								Y. pestis	Y. pseudotuberculosis	Y. enterocolitica	Shigella flexneri	Salmonella Typhimurium
CT088	CTL0343	CPn0325	CCa00457	scc1; sycE	IA	CT091/CTL0346 gene cluster encoding CdsU, LcrD, CopN	Begins 16 hpi; peaks 24 hpi, slight drop 40 hpi	None	None	None	None	SicP
CT663	CTL0032	CPn0713	CCa00029	scc4; sycE; slc\ill\	IB	CT663/CTL0032; largest T3SS gene cluster encoding 3 chaperones, 7 T3SS proteins, serine/threonine kinase pkn5	Begins 16 hpi; peaks 24 hpi, slight drop 40 hpi	None	None	None	None	None
CT043	CTL0299	CPn0387	CCa00409	slc1	IB	None	Begins 8 hpi; peak 24 hpi, slight drop 40 hpi	None	None	None	None	SicP
CT260	CTL0512	CPn0409	CCa00385	mcsc	IB	5′ of 4 Gene cluster encoding DnaQ, MqnD, and an uncharacterized protein	Begins 8 hpi; peak 24 hpi, slight drop 40 hpi	None	None	None	None	None
CT584	CTL0847	CPn0803	CCa00960	unassigned	IB	3′ End of 3 gene cluster encoding MinD and gp6D	Begins 16 hpi; peak 40 hpi	None	None	None	None	None
CT576	CTL0839	CPn0811	CCa00952	lcrH_1; scc2	II	CT576/CTL0839 gene cluster encoding CopB and CopD	Begins 16 hpi; peak 40 hpi	SycD/LcrH	SycD/LcrH	SycD/LcrH	IpgC/CesD/Syc D/LcrH family	SicA/SscA/CesD/S ycD/LcrH family
CT274	CTL0526	CPn0423	CCa00370	unassigned	II	3′ End of 2 gene cluster; first gene encodes an uncharacterized protein	Begins 8 hpi; peak 24 hpi, slight drop 40 hpi	None	None	None	None	SscB/CesD/SycD/L crH family
CT862	CTL0237	CPn1021	CCa00740	lcrH_2; scc3	II	copB2/copD2 Gene cluster	Begins 16 hpi; peak 40 hpi	SycD/LcrH family	SycD/LcrH family	SycD/LcrH family	CesD	SycD/LcrH family
CT665	CTL0034	CPn0711	CCa00031	cdsE	III/V?	CT663/CTL0032; largest T3SS gene cluster encoding 3 chaperones, 7 T3SS proteins, serine/threonine kinase pkn5	Begins 8 hpi; peak 24 hpi, slight drop 40 hpi	None	None	None	None	None
CT667	CTL0036	CPn0709	CCa00033	cdsG	III	CT663/CTL0032; largest T3SS gene cluster encoding 3 chaperones, 7 T3SS proteins, serine/threonine kinase pkn5	Begins 8 hpi; peak 40 hpi	None	None	None	None	None
CT114	CTL0369	CPn0145	CCa00623	unassigned	unkn, likely II; TPR domain aa261-462	None, but precedes incD operon	Begins 3 hpi; peaks 24 hpi, slight drop 40 hpi	None	None	None	None	None

^aDetermined by C. trachomatis serovar D genome organization.

^bTimes are relevant for C. trachomatis serovars D and L2. Information is from reference 5.

^cBLAST searches using CTL protein sequences, including PSI-BLAST.

^dGPIC C. caviae strain ATCC VR-813/DSM 19441.

^eBolded names are the most commonly used in the field.