One of the many controversies surrounding large-scale biofuel production is the diversion of land and other resources that might otherwise be used for food crops. Recent innovations will lead to a second generation of biofuel crops that can co-exist with food crops with little or no competition. Feedstocks from these bio-energy crops will be used to produce liquid fuel from cellulose, the most abundant polymer on the planet. Cell walls of higher plants are mainly composed of cellulose, hemicellulose, and lignin polymers. Cellulose and hemicellulose are polysaccharides with obvious value for biofuel production. However, lignin, while vital for plant growth and development, is widely known to negatively impact conversion efficiencies. Biomass pre-treatment, which is aimed at lignin removal, is not straightforward, and presents one of the major scientific and technical challenges and expenses associated with secondgeneration biofuel production. Scientific breakthroughs associated with altering the expression of key genes in the lignin biosynthetic pathway of biomass crops is a promising path toward solving this problem, and will likely impact the feedstock patent landscape in the near future. This review summarizes some of the recent and most important issued patents and patent applications associated with lignin-modification genes and methods of developing transgenic plants with altered lignin content and composition.
Keywords: Intellectual property, patents, second-generation biofuel, feedstock, genetic engineering, cell-wall composition, lignin, biosynthesis, content, composition, Second-Generation Biofuels, hemicellulose, lignin polymers, bio-energy, polysaccharides, lignocellulosic biomass, degradation-resistant phenolic polymer, hydrolytic enzymes, genetic engineering., BIOSYN-THESIS, Ferulate-5-Hydroxylase (F5H), F5H, the guaiacyl, syringyl, US6252135, US6489538, US6610908, US6969784, US7317136, US7429649, cauliflower mosaic virus (CaMV), F5H chimeric gene, selecting transformed cells, callus, somatic, embryos, caffeic acid/5-hydroxyferulic acid O-methyltransferase, ferulate-5-hydroxylase, (hydroxy)cinna-moyl-CoA ligase, (hydroxy)cinnamoyl-CoA reductase, anti-sense F5H, anti-sense methodology, polynucleotide, Cinnamate 4-Hydroxylase (C4H) Promoter, anti-sense, plant's lignin, plant fragment, cell, Sinapyl Alcohol Dehydrogenase (SAD), monolignol, parenchymatous storage tissue, primary phloem fibers, P450-2, gymnosperm species, loblolly pine, sweetgum P450-2, phenyl-alanine ammonia lyase, PAL, gene expres-sion, lignin monomer, Coenzyme A Ligase (4CL) Chiang et al. describe a method of altering gr, heterologous, anti-sense sequence, lignin synthesis, CCL2 Promoter, CL RNAi Constructs, double-stranded RNA (dsRNA), lignin reduction, forestry, applications, super-ubiquitin, vascular-preferred, LIM Transcription Factor, LIM transcription factors, hydroxycinnamate CoA ligase, anti-sense Ntlim1, CAld5H, AldOMT, coniferyl aldehyde 5-hydroxylase (CAld5H), Genetic Engi-neering, Syringyl-Enriched Lignin in Plants, drastic reductions, 4CL anti-sense RNA, aspen CAld5H, Hydroxycinnamoyl Transferase (HCT), 4-coumarate 3-hydroxylase (C3H), O-methyl Transferase (OMT), embryo-genic calli, chimeric ryegrass LpOmt1 gene, Phenylcoumaran Benzylic Ether Reductase (PCBER), lignan biosynthesis, WO 2004/048579 A1, US20080274528, Gas chromatography-mass spectrometry, (GC-MS) analysis, sinapic and ferulic acids, Lignin-Modulating Polypeptides, nicotinamide adenine dinucleotide (NAD), xyloglucan endo-trans-glycosylase, (XET) polypeptide, CAld5H, CCoA-3H, CCoA-OMT, plant's structural integrity, Tyrosine, Lysine, Serine, Threonine, Cysteine, lignin-protein bonds, cysteine residues, biomass, utilization, lignocellulosic plants, ROP (RAC) GTPase, guanosine triphosphate (GTP), ROPs (Rho-related GTPase, rice OsRac1, N-Acetylglucosamine Transferases, N-acetylglucosamine transferase, N-acetylglucosamine, transferase, chimeric chitin synthase gene, IP litigation