Isolation of xylose isomerases by sequence- and function-based screening from a soil metagenomic library

Table 3 Reported specific activity and maximum specific growth rate for XI genes cloned in Saccharomyces cerevisiae^a

Source of XI	Activity (U/mg protein)	Aerobic growth rate on xylose (hour^-1)	Source	Identity with *xym1* XI	Identity with *xym2* XI	Identity with *Piromyces* XI
Metagenome xym1^b	0.33 ± 0.05	0.02	This study	100%	67%	61%
Metagenome xym2^b	0.20 ± 0.04	0.02	This study	67%	100%	63%
Piromyces sp. ^b,c	0.35	0.07	This study	61%	63%	100%
Piromyces sp.	0.3 to 1.1	0.22	[18]	61%	63%	100%
Piromyces sp.^c	0.5 to 0.8	0.02	[17]	61%	63%	100%
Piromyces sp. ^c	0.0538	0.056	[16]	61%	63%	100%
Orpinomyces sp.	1.6	0.01	[15]	61%	61%	94%
Xanthomonas campestris	0.016	0.02	[44]	64%	63%	61%
Bacteroides thetaiotaomicron	0.14	n.m.	[45]	61%	64%	83%
Clostridium phytofermentans ^c	0.0344	0.057	[16]	54%	52%	54%
Clostridium thermosulfurogenes	n.m.	n.d.	[46]	51%	49%	49%
Escherichia coli	n.m.	n.d.	[19]	50%	52%	48%
Bacillus subtilis	n.m.	n.m.	[47]	48%	48%	47%
Lactobacillus pentosus	n.d.	n.d.	[47]	48%	47%	46%
Thermus thermophilus	0.0007 to 0.012	n.m.	[48]	31%	30%	29%

^an.m., not measured; n.d., not detected. Sequence identity with xym1, xym2 and Piromyces XI gene is also given at the protein level. ^bGlucose-grown cells. ^cCodon-optimised gene.

ISSN: 2731-3654