Koukol J, Conn EE (1961) The metabolism of aromatic compounds in higher plants. IV. Purification and properties of the phenylalanine deaminase of Hordeum vulgare. J Biol Chem 236:2692–2698. https://doi.org/10.1016/S0021-9258(19)61721-7 Secondary metabolism is the result of long-term evolutionary adaptation of plants to the ecological environment, and it plays an important role in dealing with the relationship between plants and the ecological environment. It enables plants to better adapt to their environment during development and to change themselves to form their unique individual characteristics ( Dangl and Jones, 2001). As a key secondary metabolic pathway, phenylpropane metabolism begins with phenylalanine and eventually leads to the production of secondary metabolites such as flavonoids, phenols and lignans ( Wang etal., 2016; Zhan etal., 2022). PAL, as an enzyme in the first reaction step of phenylpropane metabolism, plays a key and has a major impact on the subsequent secondary metabolism ( Wei etal., 2023). The number of PAL family members currently varies among plants, e.g., four PAL genes were identified in Arabidopsis, 13 in maize, nine in rice, and four in citrus. 14 and 11 were identified in cultivated tomato and S pennellii, respectively, in the present study, with numbers similar to those of the monocotyledonous plant maize. The number of SlPAL and SpenPAL genes far exceeded that of Arabidopsis, suggesting that tomato may have undergone genomic duplication events occurred during evolution ( Wanner etal., 1995; Raes etal., 2003), and tandem and fragmental duplication can be seen to have occurred in cultivated tomato and S. pennellii based on chromosomal localization and intraspecific co-linearity ( Figures1, 7). Replication events are important in the expansion and evolution of gene families and include whole genome replication, small fragment replication, local tandem replication or a combination of these possibilities ( Ober, 2005; Lei etal., 2012; Xue etal., 2012). Reichert AI, He XZ, Dixon RA (2009) Phenylalanine ammonia-lyase (PAL) from tobacco (Nicotiana tabacum): characterization of the four tobacco PAL genes and active heterotetrameric enzymes. Biochem J 424:233–242 Plants are distributed almost worldwide. While they inhabit several biomes which can be divided into a multitude of ecoregions, [79] only the hardy plants of the Antarctic flora, consisting of algae, mosses, liverworts, lichens, and just two flowering plants, have adapted to the prevailing conditions on that southern continent. [80]

Leroi, Armand Marie (2014). The Lagoon: How Aristotle Invented Science. Bloomsbury. pp.111–119. ISBN 978-1-4088-3622-4. Despres C, DeLong C, Glaze S, Liu E, Fobert PR (2000) The Arabidopsis NPR1/NIM1 protein enhances the DNA binding activity of a subgroup of the TGA family of bZIP transcription factors. Plant Cell 12:279–290 Yang, Yun Young; Kim, Jae Geun (24 November 2016). "The optimal balance between sexual and asexual reproduction in variable environments: a systematic review". Journal of Ecology and Environment. 40 (1). doi: 10.1186/s41610-016-0013-0. hdl: 10371/100354. S2CID 257092048. McElwain, Jennifer C.; Punyasena, Surangi W. (2007). "Mass extinction events and the plant fossil record". Trends in Ecology & Evolution. 22 (10): 548–557. doi: 10.1016/j.tree.2007.09.003. PMID 17919771. Bradford, M. M. (1976). A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Analytical Biochemistry, 72, 248–254.Koukol, J., & Conn, E. E. (1961). The metabolism of aromatic compounds in higher plants. Journal of Biological Chemistry, 236, 2692–2698. Numbers of threatened species by major groups of organisms (1996–2010)" (PDF). International Union for Conservation of Nature. 11 March 2010. Archived (PDF) from the original on 21 July 2011 . Retrieved 27 April 2011.

Wrench, Jason S. (9 January 2013). Workplace Communication for the 21st Century: Tools and Strategies that Impact the Bottom Line [2 volumes]: Tools and Strategies That Impact the Bottom Line. ABC-CLIO. ISBN 978-0-3133-9632-8. Biochemical defenses: secondary metabolites". Plant Defense Systems & Medicinal Botany. Archived from the original on 3 July 2007 . Retrieved 21 May 2007. Plants that have secondarily adopted a parasitic lifestyle may lose the genes involved in photosynthesis and the production of chlorophyll. [60] Growth and repair Strother, Paul K.; Battison, Leila; Brasier, Martin D.; Wellman, Charles H. (26 May 2011). "Earth's earliest non-marine eukaryotes". Nature. 473 (7348): 505–509. Bibcode: 2011Natur.473..505S. doi: 10.1038/nature09943. PMID 21490597. S2CID 4418860.Further information: Biogeography A map of a classification of the world's vegetation into biomes. Those named here include tundra, taiga, temperate broadleaf forest, temperate steppe, subtropical rainforest, Mediterranean vegetation, monsoon forest, arid desert, xeric shrubland, dry steppe, semiarid desert, grass savanna, tree savanna, subtropical and tropical dry forest, tropical rainforest, alpine tundra, and montane forests. Shown in gray is " ice sheet and polar desert" devoid of plants.

Kong JQ (2015) Phenylalanine ammonia-lyase, a key component used for phenylpropanoids production by metabolic engineering. RSC Adv 5(77):62587–62603 Sato, Motoaki (1990). "Thermochemistry of the formation of fossil fuels". Fluid-Mineral Interactions: A Tribute to H. P. Eugster, Special Publication No. 2 (PDF). The Geochemical Society. Archived (PDF) from the original on 20 September 2015 . Retrieved 1 October 2017.Lowry OH, Rosebrough NJ, Farr AL, Randall RJ (1951) Protein measurement with the Folin phenol reagent. J Biol Chem 193(1):265–275. https://doi.org/10.1016/S0021-9258(19)52451-6 Ellison, Aaron; Adamec, Lubomir (2018). "Introduction: What is a carnivorous plant?". Carnivorous Plants: Physiology, Ecology, and Evolution (Firsted.). Oxford University Press. pp.3–4. ISBN 978-0-1988-3372-7.