The origins of agriculture were traced to a period of about 10,000 years ago when the hunter-gatherer lifestyle was replaced by farming. This “green revolution” occurred in many locations and among many peoples. The diversity of foods and food compositions before and after the first green revolution suggest that fundamental genomic mechanisms exist to digest and utilize the broad spectrum of human diets. Some of the genes that express digestive enzymes, such as amylase, are about 3.5 billion years old, as old as the first living cells. Other genes, such as enterokinase, which regulates protein digestion, are as young as 0.5 billion years old (Hedges et al., 2004). These digestive genes are part of the genome of all living organisms and are essential for maintenance, growth, and reproduction (de Duve, 2007). Their generic nature permits the present and future diversity of agriculture and food availability. As pointed out the growth of global population is already placing strains on food availability and diversity. It is my contention that greater understanding of basic human food needs, when coupled to understanding of the spectrum of food genomes, can continue to evolve and sustain global population growth and health through a new green revolution.
What Is Nutrition?
Entropy is a universal physical quantity that defines the second law of thermodynamics: Energy dissipates, maximizing the disorder in the universe. However, living organisms defy the decay into equilibrium with the environment by feeding on negative entropy and decreasing their disorder. By living, the organism maintains itself in a stationary or low level of entropy (Schrödinger, 1956, p. 73). Nutrition is the process by which the organism is continually consuming negative entropy from the environment. In humans, the ingested negative entropy consists of foods. Here, we examine the genomic history of the processes of digesting the negative entropy contained in food macronutrients: proteins, fats, and carbohydrates. In plants, the most powerful supply of negative entropy is from sunlight. All living organisms concentrate a “stream of order” from the environment to escape the atomic chaos of entropy and display the power of maintaining self and expressing orderly events (p. 75). These interwoven events are guided by genetic mechanisms that are completely at odds with the “probabilistic mechanisms” of physics to ensure the living paradigm of orderliness. Growth and reproduction are due to an “order-from-order” principle (p. 78). The genome thus defies the disorder of the physical universe. A fundamental difference between the physical and biological universes is the harmony that bridges the genome of single with multicellular organisms. By defying the laws of physics, living cells were described as “the finest masterpiece ever achieved along the lines of the Lord’s quantum mechanics” (p. 83).
What Is the History of Life?
Planet earth is thought to have formed about 4.5 billion years ago (bya). The common ancestor of contemporary life forms populated the earth about 3.5 bya (Pollard et al., 2008, p. 17). Biochemical features stored in all present life forms suggest that this primitive microscopic cell had about 600 genes encoding DNA, protein synthetic machinery, and a plasma membrane and with mechanisms for digesting polymeric molecules and assimilating negative entropy from the environment. Over about 1.7 bya, distinctive living species evolved. On the basis of evolutionary records, preserved in their genomes, living organisms are divided into three primary domains: archaea, bacteria, and eukarya. Genomic diversification evolved by mutation, duplication, and divergence, and lateral transfer of DNA (p. 19). Photosynthesis originated about 3 bya by symbiosis by two different families of bacteria. About 2.5 bya, a lateral transfer event brought the two genomes for photosynthesis together in cyanobacteria (blue-green algae). Sunlight energized the photosynthetic structures to activate a proton gradient used to synthesize adenosine triphosphate (ATP) and the many carbon compounds that living organisms required for negative entropy. About 2.4 bya, cyanobacteria produced most of the oxygen in the Earth’s atmosphere as the product of photosynthesis. This increase in oxygen revolutionized the chemical environment for all other species of organisms.
Genomic history indicates that the present eukaryotic lineages diverged between 2 and 1 bya (Hedges et al., 2004; Figure 2.1). Cell surface membranes characterize both eukaryotes and prokaryotes; however, internal compartmentalization is lacking in prokaryotes. The external membrane of prokaryotes separates digestion of macromolecules outside the cell from internal machinery requiring these nutrients. These primitive cells exert digestion by exporting enzymes, either by secretion or extension from the cell surface, to hydrolyze complex organic structures. The products of digestion are then processed and ingested through the membrane for metabolic processes (de Duve, 2007). Compartmentalization of internal cell structures is thought to have evolved by the regional segregation of digestive enzymes on the external surface of the plasma membrane, a feature persistent in present-day bacteria. Invagination of the segregated domains of plasma membrane likely generated the membrane-bound organelles of eukarya.
One hypothesis is that cells from the prokaryotes joined in a symbiotic relationship to generate the first eukaryotes about 2.7 bya. Later, lateral transfer of the genome was surrounded by plasma membrane to become the eukaryotic nucleus. Genomic evidence has established that eukaryotes acquired mitochondria about 1.8 bya when a protobacterium became symbiotic. The bacterial genome thus contributed molecular machinery for ATP synthesis by oxidation phosphorylation. Over many centuries of evolution, most symbiotic bacterial genes moved into the host cell nucleus.
The acquisition of chloroplasts began when the cyanobacterial symbiant brought photosynthetic machinery into a primitive algal cell that had mitochondria by lateral transfer about 1.6 bya. Symbiosis evolved into interdependence when the chloroplast genes were assimilated into the nuclear genome. About 2 bya, the algal and plant branches of eukarya evolved independent strategies for multicellular existence. Further increases in organism cell number occurred about 1.5 bya (Hedges et al., 2004). Fossils confirm that animals had evolved multicellular structures by 0.6 bya. These primitive metazoans (multicell organisms) had mouth, intestine, and sensory structures. Evolution of genes for intercellular adhesion proteins pre-dated the metazoan animals. The early metazoan animals resemble contemporary animal embryos in appearance. In this period, animals diverged into the three subdivisions: mollusks, annelid worms, bracheopods, and platyhelminths (~1.3 bya); arthropods and nematodes (~1 bya); and echinoderms and chordate (~0.5 bya, humans at ~ 0.06 bya) (Hedges et al., 2004; Pollard et al., 2008, p. 17).
Genomic History of Digestion
Here, we review the evolution of the major digestive processes that demark the boundary between human negative entropy intake (food) and nutrient utilization (metabolism). The macronutrients are viewed as purveyors of essential food micronutrients. We trace the genomic history (phylogenies; Huerta-Cepas et al., 2007) of the major human digestion enzymes. As described, digestion was well established in the prokaryotic organisms at 3.5 bya and advanced to a compartmentalized system in early eukarya by 2 bya. In fossil metazoan animals, a gastrointestinal tract was evidenced by 0.6 bya.
Protein Digestion
The central dogma of molecular biology is that DNA is transcribed into RNA, and this RNA is translated into proteins (Pollard et al., 2008, p. 251). Thus, proteins are most tightly controlled by the genome. This dogma has significance for the protein substrates and the digesting enzymes converting food into oligopeptides and free amino acids for absorption. The synthesis of all proteins is called translation because of the conversion of the genetic code into amino acids in the peptide chain by messenger RNA (mRNA). Small transfer RNA (tRNA) is the purveyor of specific amino acids in response to successive codons within the mRNA. The codons are made up of three nucleic acids whose sequence is transcribed from genomic DNA. The genetic code converting the information from codons into amino acid sequence is almost universal. Thus, the four nucleotides in the genome are expanded to 64 different triplet codons, resulting in 20 specific amino acid translations. One codon specifies the start, and three specify the stop of coding. The mRNA translation takes place in ribosomes in the cytoplasm of prokaryotes and the endoplasmic reticulum (ER) of eukaryotes. Resulting soluble proteins are folded by mechanisms encoded in the sequence but are sensitive to cytoplasmic physical conditions. Transmembrane protein folding is frequently assisted by molecular chaperones that inhibit aggregation and assist sorting to cellular organelles and membrane domains such as the lumen of the digestive tract. Many cell surface proteins are glycosylated in the Golgi as a processing step; more than 200 enzymes orchestrate the addition of sugar residues to peptides. Glycoproteins are important for cell adhesion and are highly resistant to digestion.
Adult humans consume about 50 g/d of protein. About 90% of this intake is digested to absorbable peptides and amino acids in the upper intestine (Erickson and Kim, 1990;). A series of different peptidases participate in this digestion process (Erickson and Kim, 1990). Gastric pepsin is an endoprotease hydrolyzing an aspartic residue in the peptide sequence (Whitcomb and Lowe, 2007). This human chromosome 11 paralogous gene with multiple isoforms is limited in expression throughout animal phylogeny, suggesting a common ancestor before differentiation of the arthropods about 1.5 bya (Benson et al., 2008). A bovine homologue, renin, is an enzyme used for making cheese by precipitation of milk caseins.
The pancreatic peptidases include trypsin, chymotrypsin, and elastin (Whitcomb and Lowe, 2007). The trypsins are a family of secreted serine endoproteases coding from nine genes on chromosome 7 and one on chromosome 9. The genes are embedded within T-cell receptor beta (TCR-B) loci of both chromosomes. The multiple-protein isoforms from chromosome 7 trypsins have redundant secreted activities; however, that from chromosome 9 is more resistant to inhibitors (Benson et al., 2008). An association with TCR-B is present throughout mammals from about 0.2 bya, but the gene itself is rooted in many bacterial species and thus was present from as long as 1.1 bya. Chymotrypsin is another secreted pancreatic serine endoprotease. It is coded from a duplicated gene located on chromosome 16 and is a neighbor of two more pancreatic elastase serine endoprotease genes on chromosome 1. The phylogeny of these chymotrypsin and elastase genes is parallel to that of trypsin, with a secreted presence in bacteria and conservation of associated genes on chromosomes on mammalian species. The pancreas also produces a family of secreted carboxypeptidase exoproteases. Carboxypeptidase A is expressed as two isoforms and cleaves terminal aromatic amino acids; carboxypeptidase B cleaves terminal aliphatic amino acids. Both are zinc-requiring metalloproteases. These reside on human chromosome 7 within a cluster of four genes, two of which are specific for the pancreas. The genomic context of these human pancreatic proteolytic enzymes is conserved within rodent chromosomes, which diverged about 0.3 bya, and the phylogenic roots extend back to bacteria that evolved about 2 bya. These secreted digestive gene products are likely rooted in the genome of the common ancestor of all cell lineages (de Duve, 2007).
The final steps of digestion of food proteins to absorbable peptides and free amino acids take place at the lumenal membrane of small intestinal enterocytes (Sterchi and Woodley, 1980a, 1980b; Sterchi, 1981; Rawlings et al., 2008). The lumenal brush border membrane anchors a series of peptidases, most of which hydrolyze terminal amino acids. Enterokinase has the specialized function of activating the secreted pancreatic proteases described. It has a younger phylogeny than the remaining enzymes. The remaining peptidases are expressed in many tissues, including T cells, and are identified by CD antigen numbers. These membrane enzymes often play a role in the regulation of peptide hormone blood levels and are targets for pharmacologic inhibitors. γ-Glutamyl peptidase is a key enzyme in the glutathione cycle and plays a critical role in xenobiotic detoxification. The last five enzymes diverged before bacterial emergence (2.5 bya) and likely are descendants from membrane-bound digestive genes expressed by the first common ancestor of life (de Duve, 2007).
Lipid Digestion
A surrounding membrane contributes to the defiance of entropy by the living cell. This is a planar structure composed of phosphodiglycerides oriented to display hydrophilic PO4 external extensions coating a core of hydrophobic diglyceride tails (Pollard et al., 2008, p. 113). Other lipids are also embedded into the external faces, and hydrophobic membrane proteins and transporters traverse the lipid core. The membrane is stable and relatively impermeable to ions and electrons. It is believed that the earliest life forms evolved the lipid membrane to decrease local entropy within a living cell about 3.5 bya. All sequenced genotypes have conserved enzymes that catalyze the synthesis of coenzyme A and mevalonate in the synthetic pathway to phosphodiglycerides and cholesterol (Friesen and Rodwell, 2004). By contrast, only eukaryotes synthesize neutral triglycerides, which are stored as intracellular hydrophobic droplets (Turkish and Sturley, 2007). These membrane and stored lipid classes are major contributors to food negative entropy. The disorders of atherosclerosis and obesity are thought to be influenced by quality and quantity of lipids in foods. The glycerides are not primary products of DNA transcription, as are proteins, but are products of regulated multienzyme metabolic pathways; the consequence is the synthesis of a family of di- and triglycerides with fatty acids ranging from 14 to 20 carbons in length with variable degrees of saturation.
The adult Western diet contains about 100 g/day of fat, of which more than 90% exists as triglycerides. Virtually all food triglycerides and diglycerides require lumenal small intestinal digestion before more than 95% absorption (Lowe 1997, 2002). This is accomplished by a series of lipase enzymes. Lipases are esterases that can hydrolyze acyltriglycerides into di- and monoglycerides, glycerol, and free fatty acids at a water-lipid interface. Gastric lipase is the initial digesting activity hydrolyzing position 3 (sn-3) ester linkages of the glycerides. This is a developmentally important enzyme for normal young human infants, who have a physiological delay in maturation of pancreatic lipase. The human enzyme is transcribed from chromosome 10, where it resides within a cluster of five paralogous genes. This gastric lipase chromosomal grouping is conserved in rodents. The gastric expressed gene is only found in eukaryotes. Pancreatic triglyceride lipase (PTL) is the second and major lipase that hydrolyzes all sn-1 and sn-3 esters of acylglycerides but not membrane lipids. Pancreatic lipase is also on human chromosome 10 within a locus of four paralogs whose relationship is conserved in rodents. One of these paralogous genes produces an 80% homologous pancreatic lipase-related protein (PLRP2), which hydrolyzes acyltriglycerides and all membrane lipids. Both pancreas-expressed genes are only found in eukaryotes. Both proteins have two domains: N-terminal and C-terminal. The N-terminal is associated with interfacial activation, the process of becoming active at the lipid-water interface. The function of the C-terminal is to mediate interaction with lipids. Many food components inhibit pancreatic lipase, and the pancreas secretes colipase, which conserves activity by functioning as a PTL cofactor. Colipase binds to the bile-salt covered triacylglycerol interface thus allowing the PTL enzyme to anchor itself to the water-lipid interface. Colipase gene is located on chromosome 6 and only found in eukaryotes. The locus is conserved on the mouse chromosome. In mouse knockout (KO) studies, PTL deficiency was asymptomatic, but colipase deficiency was associated with steatorrhea.
Bile salt-dependent lipase is also secreted by the pancreas. This enzyme has broad substrate specificity for all fat and membrane lipids. It is also secreted in human milk. This enzyme codes from human chromosome 9 and is conserved in archael and bacterial genomes. Phospholipase A2 (PLA2) is a secretory pancreatic enzyme that cleaves the sn-2 position of the glycerol backbone of membrane phospholipids. It is clustered with two paralogs on chromosome 1 and is also expressed on placenta, synovial membranes, and platelets. PLA2 is only expressed in eukaryotes. Knockout of the last two specific genes in mice was not associated with steatorrhea, suggesting that the overlapping substrate specificities of the various lipases are redundant, and that individual deficiencies are compensated by the remaining lipases.
Carbohydrate Digestion
The carbohydrates are a major source of negative energy in the human diet; some rural agricultural workers consume more than 500 g/day (Robayo-Torres et al., 2006,). The amount digested in the small bowel is dependent on the species of carbohydrate fed; the range is from more than 95% down to less than 30% with digestion-resistant starches (described in the section α-Glucosidase Digestion of Starch). Food carbohydrates exist as glycosides bound to membrane proteins and lipids and as sugar units of disaccharides and glucose polymers. In the first category, the carbohydrates provide stability to the lipid-water plasma membrane (Pollard et al., 2008, p. 113). The second case provides stored energy-rich foods that ensure adequate glucose for prandial metabolism.
Milk Sugar
Lactose is the principal carbohydrate in milk (Robayo-Torres et al., 2006). It is a disaccharide composed of glucose and galactose linked as 1-β-D-galactopyranosyl-4-α-D-glucopyranose. N-Acetyllactosamine synthase is highly conserved, with seven paralogous genes on various chromosomes and is a component of lactose synthase along with α-lactalbumin (chromosome 12). The N-acetyllactosamine synthase is ahighly conserved gene in all genomes. In contrast, the α-lactalbumin gene is limited to mammalian genomes but has an ancestral root as a lysosomal enzyme gene. N-Acetyllactosamine synthase is expressed in seven isoforms and plays a crucial role in protein N-glycosylations. As lactose synthase complex, these two genes are central to human and bovine lactation, for which lactose production drives the volume of milk produced.
Small intestinal mucosal lactase is the hydrolase that digests lactose to the monosaccharide units. The lactase protein is an internally duplicated enzyme that belongs to the glycosyl hydrolases family GH 1 (Benson et al., 2008). The enzyme is bound at the C-terminal to enterocyte lumenal plasma membrane and has both lactase and phlorizin hydrolase activity. The second activity also hydrolyzes β-glucosides of lipids and micronutrients such as pyridoxine-5′-β-D-glucoside and other glycosylated phytochemicals. The enzyme has a glutamic acid proton donor and glutamic acid nucleophile and a (β/α)8 barrel structure. In the human, the gene for lactase activity is down regulated at about 4 years of age, resulting in symptomatic lactose intolerance. A mutation in regulation of this gene permits lactase persistence in adults, and onset of the mutation is correlated with the development of dairy cattle about 10,000 years ago. Symptoms of lactose intolerance are treated by elimination of lactose in the diet or by oral lactase enzyme supplementation (Robayo-Torres et al., 2006).
Table Sugar
Sucrose is a disaccharide composed of glucose and fructose: α-D-glucopyranosyl β-D-fructofuranoside (Robayo-Torres et al., 2006). The sweetness, for which it is favored in candy and pastries, arises from the fructose unit. It is hydrolyzed to monosaccharides by small intestinal membrane-bound sucrase-isomaltase (SI) activity. The two subunits are both glucohydrolase family 31 α-glucosidase activities that play a prominent role in the digestion of starch. Given that sucrose only became available as a cultivated crop about 4000 years ago, the role in starch digestion is likely its primitive function. SI is bound to the membrane by the isomaltase containing N-terminal. The human SI gene is located on chromosome 2 in a context conserved among rodents. The family GH 31 genome extends throughout the archaea, bacteria, and plant kingdoms (Benson et al., 2008). In rodents, SI intestinal activities are low until the time of weaning to a starch-based diet. A human disorder, congenital sucrase-isomaltase deficiency (CSID) has been discovered with clinical symptoms similar to lactose intolerance. These patients are relieved if sucrose is removed from the diet or an oral supplement of sucrase enzyme is fed with the sugar. Some CSID patients also have symptoms when fed starch (Robayo-Torres et al., 2006).
Starch Digestion
The plant kingdom converts radiant to chemical negative energy by fixation of atmospheric CO2 through photosynthesis by leaf chloroplasts (Quezada-Calvillo et al., 2007a, 2007b). The immediate product of carbon fixation by chloroplasts is starch, which is synthesized in light and degraded in dark cycles. The disaccharide sucrose is produced in leaf cytosol from starch-derived adenosine diphosphate (ADP)-glucose. Sucrose is then transported from leaves to amyloplasts in reproductive tissues, where it is converted to storage molecules composed of thousands of polymeric glucose units. Starches with mostly linear α-1,4 glucose linkages are known as amyloses, and those with a mixture of α-1,4 and α-1,6 branched linkages are amylopectins. In the plant, these are stored as chemical energy within semicrystalline granules whose glucose units become available during reproduction. Plant cell walls are composed of β-linked glucoside (cellulose) and nonglucose polymers that are poorly digested by the human small intestine; these carbohydrates are classed as dietary fibers. These polymers are not primary products of DNA transcription but are products of regulated multienzyme metabolic pathways; the product is synthesis of a family of starch and fiber polymers varying in size.
Starches are a gift of the vegetable kingdom to animal diets and a major food source of negative entropy. However, animal digestion is made complicated by the hundreds of botanical varieties of food starches. In contrast to the digestion of sucrose by a single mucosal enzyme, starch digestion requires a committee of six enzymes. The multiplicity of animal starch-digesting enzymes mirrors the multiplicity of the starch synthetic enzymes of plants (Quezada-Calvillo et al., 2007a, 2007b). Amylase was the first enzyme ever identified by biochemists. The activity is increased by the process of malting by sprouting grain. The same enzyme activity is found in animal salivary and pancreatic secretions. The product maltose was first discovered in malted grains, and mucosal maltase activity was found by brewers. Four different membrane-bound maltase enzyme activities of the small intestine can be identified. Two are associated with SI activities and two lack any other identifying activities (maltase-glucoamylase, MGAM). Because the four mucosal maltase enzymes hydrolyze the nonreducing end of all α-1,4 glucose oligomers to free glucose, here they are referred to as α-glucosidase activities.
Amylase Solubilization of Starch
The Amylase gene (AMY) is highly represented in 615 species of bacteria and vertebrates. It is α-endoglucosidase and a member of family GH 13 (Stam et al., 2006; Benson et al., 2008). The gene is found in some archaea, suggesting differentiation before 2.5 bya. The human gene is on chromosome 2, where six paralogs are found (Quezada-Calvillo et al., 2007a). The grouping with neighboring genes is conserved in rodents. The secreted enzyme has a glutamic acid proton donor and aspartic acid nucleophile and a (β/α)8 barrel structure. It requires bound calcium and chloride ions for activity. The catalytic action is on internal α-1,4 linkages of starch granules, and the hydrolyzed products are a mixture of soluble maltodextrins. When there is no remaining hydrolysis possible, the produced oligomers are referred to as α-limit dextrins. The amylase activities produce very little free glucose during hydrolysis of starch granules (Quezada-Calvillo et al.). The redundant nature of the root gene expression of this secreted protein suggests that it coded digestion by the most primitive cells (de Duve, 2007).
α-Glucosidase Digestion of Starch
The most active mucosal α-glucosidase is the C-terminal of MGAM, which is located on human chromosome 7. This gene is in family GH 31 along with the complimentary gene SI (as discussed in the starch digestion section). The genes for GH 31 are expressed in 491 species, including archaea and bacteria (Sim et al., 2008;). It is not possible to differentiate GH 31 substrate specificities from genome sequences (Benson et al., 2008). Both enzymes are internally duplicated, have two catalytic sites, and are bound to the enterocyte membrane at the N-terminal (Quezada-Calvillo et al., 2007a, 2007b). MGAM and SI both have two aspartic acid proton donors and aspartic acid nucleophiles in a (β/α)8 barrel structure. Both enzymes are exoglucosidases that can hydrolyze granular starch, but the rate of glucose production is amplified fivefold if starch is also treated by AMY. The rate of α-glucogenesis from maltodextrins and α-limit dextrins by MGAM is tenfold greater than SI, but MGAM is inhibited by lumenal substrates and SI is not. This suggests that although sharing the same substrates, MGAM accelerates glucogenesis on low-starch diets, and SI constrains glucogenesis after higher starch intakes (Quezada-Calvillo et al., 2007b).
The concept of glycemic index (GI) of foods was introduced in the 1980s (Englyst et al., 2007). The GI is calculated by comparing the rise of blood glucose of fasting individuals after a test meal with the rise after a glucose feeding. Resistant starches (RSs) have been defined as “the sum of starch and products of starch degradation not absorbed in the small intestine of healthy individuals.” An in vitro analysis of rates of digestion of foods to glucose has been developed, and it is reported that rapidly available glucose (RAG) correlates with the GI (Englyst et al.). The nature of slowly available glucose (SAG) in the assay has been investigated with various starches; granular, supramolecular, and molecular structures of botanical starch species all determine the ratio of RAG to SAG (Zhang et al. 2006a, 2006b, Ao et al. 2007a, 2007b). Increasing the number of branches and reducing the length of chains increases SAG (Ao, 2007a, 2007b). In vitro mucosal α-glucogenesis of mice is slowed by experimental molecular adjustments of starch structure that are only partially restored by amylase activity (Quezada-Calvillo et al., 2007a, 2007b). Further investigations are needed to clarify the starch chemistry and enzyme molecular mechanisms behind resistant food starches because of suspected roles of starch digestion in glucose disorders such as type 2 diabetes and obesity.
Summary
The study of genomics leads to the conclusion that
• The human shares a common ancestry with other life-forms.
• The genomic roots of some human genes for secreted and membrane-bound digestive proteins were present in archael organisms about 3.5 bya. Others appeared when bacteria diverged from archaea about 2.5 bya. Others only appeared when eukarya appeared about 1 bya.
• By the time of divergence of the human from rodent genomes at 0.06 bya, the loci of digestive genes in chromosomal neighborhoods became fixed.
• The enzymes expressed by genes most essential for digestion and assimilation of negative energy often have redundancies at genome and activity levels for the important digestive enzymes, such as γ-glutamyl transpeptidase, which ensure normal phenotypes in the face of individual coding mutations. Where no genomic redundancy exists, as with dipeptidyl peptidase IV, mutated genes can result in clinical disorders.
• Some may express reservations about the religious implications of the genomic roots of our nutritional heritage. In the words of Francis Collins, director of the National Institutes of Health (NIH) Genome Project, “The God of the bible is also the God of the genome” (Collins, 2006, p. 211;).
• The online GenBank of the NIH Genome Project presently contains over 65 billion nucleotide bases from more than 61 million individual sequences. Over 240,000 named species are represented, and only about 16% of the sequences are of human origin. The number of complete sequences of genomes of food plants and animals is rapidly expanding (Benson et al., 2008).
• Agriculture production was critical in the past 10 to 12 thousand years as food crops were developed to provide negative entropy through phenotype selection. This process supported the growth of civilizations.
• Given a better precision in understanding of human negative energy needs and with the expanding genomic understanding of crop phenotypes, we can envision future advances in genetically characterized foods that satisfy expanding global human needs for quality and quantity and sustain agricultural ecology).
• Genetically modified organisms (GMOs) are already accepted in much of the world and hold the promise to resolve much of the existing discrepancies between food availability and human negative energy needs.
By Buford L. Nichols and Roberto Quezada-Calvillo in "Adequate Food for All:Culture, Science, and Technology of Food in the 21st Century", editors Wilson G. Pond, Buford L. Nichols, and Dan L. Brown, CRC Press, USA, 2009, excerpts p.15-28. Adapted and illustrated to be posted by Leopoldo Costa.