英国研究人员报告说,他们发现一种细菌具有分解木头和其他植物中木质素的能力,这有助于利用树木枝干和农作物收获后剩下的茎秆来提炼生物燃料。
树木枝干和许多植物的茎秆通常含大量难以分解的木质素,因此利用它们来提炼生物燃料的效率要大打折扣。
英国沃里克大学等机构研究人员在新一期《生物化学》(Biochemistry)上报告说,一种红球菌或许能帮助解决这一问题,因为它能分泌一种具有分解木质素能力的酶。
研究人员说,以前曾发现某些真菌也能分泌类似的酶,但本次研究首次发现有细菌能分泌这种酶。细菌比较容易培养,并且这种红球菌的基因组早已完成测序,可以较方便地使用基因手段来改变这种细菌,从而利用它大规模生产分解木质素的酶。
研究负责人蒂莫西·布格教授说,现在发展生物燃料的一个方向就是不与粮食生产冲突,而是利用废弃的茎秆等提炼生物燃料,这项研究成果可望用来在工业化程度上大规模分解木质素,非常有助于生物燃料的发展。(生物谷Bioon.com)
生物谷推荐原文出处:
American Chemical Society DOI: 10.1021/bi101892z
Identification of DypB from Rhodococcus jostii RHA1 as a Lignin Peroxidase
Mark Ahmad, Joseph N. Roberts, Elizabeth M. Hardiman, Rahul Singh, Lindsay D. Eltis, and Timothy D. H. Bugg
Rhodococcus jostii RHA1, a polychlorinated biphenyl-degrading soil bacterium whose genome has been sequenced, shows lignin degrading activity in two recently developed spectrophotometric assays. Bioinformatic analysis reveals two unannotated peroxidase genes present in the genome of R. jostii RHA1 with sequence similarity to open reading frames in other lignin-degrading microbes. They are members of the Dyp peroxidase family and were annotated as DypA and DypB, on the basis of bioinformatic analysis. Assay of gene deletion mutants using a colorimetric lignin degradation assay reveals that a ΔdypB mutant shows greatly reduced lignin degradation activity, consistent with a role in lignin breakdown. Recombinant DypB protein shows activity in the colorimetric assay and shows Michaelis–Menten kinetic behavior using Kraft lignin as a substrate. DypB is activated by Mn2+ by 5–23-fold using a range of assay substrates, and breakdown of wheat straw lignocellulose by recombinant DypB is observed over 24–48 h in the...