Table 2.

Summary of Francisella chitinase bioinformatics and activities

Francisella group	Chitinase class	Predicted pseudogenea	Recombinant activity	In vitro production
F. tularensis
A1a/A1b	ChiA	No	+	+
	ChiB	No*	+	–
	ChiC	Yes/Yes†	–/+	–
	ChiD	No	–	NTb
A2	ChiA	Yes‡	NT	–
	ChiB	Yes§	NT	–
	ChiC	No	+	+
	ChiD	No	–	NT
Type B	ChiA	No	+	+
	ChiB	No	+	+
	ChiC	No¶	–	–
	ChiD	No	–	NT
F. novicida	ChiA	No	+	+
	ChiB	No	+	+
	ChiC	No#	NT	–
	ChiD	No	–	NT

^aThe pseudogene designation is based on existing notations made to the annotated genome sequences. *, F. tularensis A1a/A1b ChiB has an N-terminal truncation resulting in deletion of the signal peptide and the N-acetylglucosamine-binding protein A domain but does not impact the GH18 domain. †, F. tularensis A1a/A1b chiC contains a point mutation that causes a premature stop codon and results in two predicted open reading frames. One reading frame (FTT_1592c) encodes an unaltered GH18 domain. ‡, F. tularensis A2 chiA is truncated due to a mutation resulting in a premature stop codon; the GH18 domain is missing. §, F. tularensis A2 chiB is truncated due to a mutation resulting in a premature stop codon; the GH18 domain is missing. ¶, F. tularensis type B ChiC contains a C-terminal truncation of that impacts the GH18 domain, but its gene is not annotated as a pseudogene. #, F. novicida strain GA99-3550 did not encode chiC. However, F. novicida GA99-3548 encoded a chiC whose product was predicted functional.

^bNT, not tested.