Altermann Eric, Schofield Linley R, Ronimus Ron S, Beatty Amy K, Reilly Kerri
Rumen Microbiology, Animal Science, AgResearch Ltd., Palmerston North, New Zealand.
Riddet Institute, Massey University, Palmerston North, New Zealand.
Front Microbiol. 2018 Oct 9;9:2378. doi: 10.3389/fmicb.2018.02378. eCollection 2018.
Methane is a potent greenhouse gas, 25 times more efficient at trapping heat than carbon dioxide. Ruminant methane emissions contribute almost 30% to anthropogenic sources of global atmospheric methane levels and a reduction in methane emissions would significantly contribute to slowing global temperature rises. Here we demonstrate the use of a lytic enyzme, PeiR, from a methanogen virus that infects M1 as an effective agent inhibiting a range of rumen methanogen strains in pure culture. We determined the substrate specificity of soluble PeiR and demonstrated that the enzyme is capable of hydrolysing the pseudomurein cell walls of methanogens. Subsequently, was fused to the polyhydroxyalkanoate (PHA) synthase gene and displayed on the surface of PHA bionanoparticles (BNPs) expressed in one-step biosynthesis. These tailored BNPs were capable of lysing not only the original methanogen host strain, but a wide range of other rumen methanogen strains Methane production was reduced by up to 97% for 5 days post-inoculation in the assay. We propose that tailored BNPs carrying anti-methanogen enzymes represent a new class of methane inhibitors. Tailored BNPs can be rapidly developed and may be able to modulate the methanogen community with the aim to lower ruminant methane emissions without impacting animal productivity.
甲烷是一种强效温室气体，其捕获热量的效率是二氧化碳的25倍。反刍动物的甲烷排放对全球大气甲烷水平的人为来源贡献了近30%，减少甲烷排放将对减缓全球气温上升做出重大贡献。在这里，我们展示了一种来自感染M1的产甲烷菌病毒的裂解酶PeiR，作为一种有效试剂，可在纯培养物中抑制一系列瘤胃产甲烷菌菌株。我们确定了可溶性PeiR的底物特异性，并证明该酶能够水解产甲烷菌的假肽聚糖细胞壁。随后，将其与聚羟基脂肪酸酯（PHA）合酶基因融合，并展示在一步生物合成中表达的PHA生物纳米颗粒（BNP）表面。这些定制的BNP不仅能够裂解原始的产甲烷菌宿主菌株，还能裂解多种其他瘤胃产甲烷菌菌株。在该试验中，接种后5天内甲烷产量降低了97%。我们提出，携带抗产甲烷菌酶的定制BNP代表了一类新型甲烷抑制剂。定制的BNP可以快速开发，并且可能能够调节产甲烷菌群落，以降低反刍动物的甲烷排放，同时不影响动物生产力。
