Table 2.
Chloroplast bioreactors for proteins/enzymes for biofuel production
| Protein/enzymes | Source of transgene | Enzyme activity | Refs |
|---|---|---|---|
| Beta glucosidase | Trichoderma. reesei | Chloroplast-derived enzymes showed wider pH optima and higher temperature stability than enzymes expressed in E. coli. Chloroplast-derived crude-extract enzyme cocktails yielded more (up to 3625%) glucose from citrus peel, filter paper or pine wood than commercial cocktails. | [32] |
| Swollenin | T. reesei | ||
| Xylanase | T. reesei | ||
| Acetyl xylan esterase | T. reesei | ||
| Endoglucanase | T. reesei | ||
| Endoglucanase | C. thermocellum | ||
| Exoglucanase | C. thermocellum | ||
| Lipase | M. tuberculosis | ||
| Pectate lyase A | F. solani | ||
| Pectate lyase A | F. solani | ||
| Pectate lyase A | F. solani | ||
| Cutinase | F. solani | ||
| β-glucosidase BglC | T. fusca | Chloroplast-produced BglC was active against both cellobiose and lignocellulose. | [87] |
| β-glucosidase Bgl 1 | T. reesei | Chloroplast-produced | [46] |
| Bgl1 could digest pNPG substrate and release p-nitrophenol. | |||
| Xylanase Xyl10B | T. maritima | Catalytic activity of chloroplast derived Xyl10B in poplar, sweetgum and birchwood xylan and stable in dry leaves. | [62] |
| β-glucosidase Bgl1C | T. fusca | All four enzymes were highly active and hydrolyzed their synthetic test substrates in a dose-dependent manner. Also, the enzyme cocktail triggered efficient sugarrelease from straw. | [96] |
| Endoglucanase Cel 9A | T. fusca | ||
| Exoglucanase Cel 6B | T. fusca | ||
| Xyloglucanase Xeg74 | T. fusca | ||
| β-Mannanase | T. reesei | Chloroplast-derived mannanase showed 6–7 fold higher enzyme activity than E. coli extracts. The enzyme cocktail with chloroplast derived mannanse yielded 20% more glucose equivalents from pinewood than the cocktail without mannanase. | [51] |
| Cutinase or swollenin | Fusarium solani | Treatment of cotton fiber with chloroplast-derived swollenin showed enlarged segments and the intertwined inner fibers were irreversibly unwound due to expansin activity of swollenin. Chloroplast derived cutinase showed esterase and lipase activity. | [97] |
| T. reesei | |||
| β-1,4-endoglucanase | Pyrococcus horikoshii | Chloroplast-derived EGPh was recovered from dry leaves and digested carboxymethyl cellulose (CMC) substrate. | [98] |
| Xylanase | Bacillus sp. | Catalytic activity of chloroplast produced Xylanase was detected with birch wood xylan as substrate | [99] |