Update 01-introduction.md

I expand the introduction, and include a table of six group NP classification

_episodes/01-introduction.md

@@ -13,6 +13,29 @@ keypoints:
 - "Natural products are encoded in Biosynthetic Gene Clusters (BGCs)"
 - "Genome mining describes the exploitation of genomic information with specialized algorithms intended to discover and study BGCs"
 ---
+## What is Genome Mining?
+
+In bioinformatics, genomic mining is defined as the computational analysis of nucleotide sequence data based on the comparison and recognition of conserved patterns. Under this definition, any computational method that involves searching for and predicting physiological or metabolic properties is considered part of genomic mining. The specific focus of genomic mining, when applied to natural products (NPs), is centered on the identification of biosynthetic gene clusters (BGCs) of NPs.
+
+Natural products (NPs) are low molecular weight organic molecules that encompass a wide and diverse range of chemical entities with multiple biological functions. These molecules can be produced by bacteria, fungi, plants, and animals. Natural products (NPs) thus play various roles that can be analyzed from two main perspectives:
+
+- **Biological function**: This refers to the role the molecule plays in the producing organism.
+- **Anthropocentric function**: This focuses on the utility of NPs for humans, including their use in medicine, agriculture, and other areas.
+
+Currently, more than 126,000 NPs are known to originate from various sources and are classified into six main groups.
+
+These groups are defined based on their chemical structure, the enzymes involved in their synthesis, the precursors used, and the final modifications they undergo. 
+ Here is the translated table:
+
+| **Class**                                                        | **Description**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | **Example**          |
+|------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------------|
+| **Polyketides (PKs)**                                             | Polyketides are organic molecules characterized by a repetitive chain of ketone (>C=O) and methylene (>CH2) groups. Their biosynthesis is similar to fatty acid synthesis, which is crucial to their diversity. These versatile molecules are found in bacteria, fungi, plants, and marine organisms. Notable examples include erythromycin, an antibiotic used to treat respiratory infections, and lovastatin, a lipid-lowering drug that reduces cholesterol. In summary, polyketides have a structure based on the repetition of ketone and methylene groups, with significant medical and pharmacological applications.                                                                                                                                                                                                                   | **Erythromycin**      |
+| **Non-Ribosomal Peptides (NRPs)**                                | NRPs are a family of natural products that differ from ribosomal peptides due to their non-linear synthesis. Their main structure is based on non-ribosomal modules, which include three key domains: Adenylation, acyl carrier, and condensation domain. Relevant examples include Daptomycin, an antibiotic widely used in various infections. Its NRP structure contributes to its antimicrobial activity. Cyclosporine is an immunosuppressant used in organ transplants. Its NRP structure is crucial to its function. In summary, NRPs feature a non-linear modular structure and play a significant role in medicine and chemical biology.                                                                                                                                                                    | **Daptomycin**        |
+| **Ribosomally synthesized and Post-translationally modified Peptides (RiPPs)** | RiPPs are a diverse class of natural products of ribosomal origin. These peptides are produced in the ribosomes and then undergo enzymatic modifications after their synthesis. Historically, RiPPs were studied individually, but in 2013, uniform naming guidelines were established for these natural products. RiPPs include examples such as Microcin J25, an antibacterial RiPP produced by *Escherichia coli*, and Nisin, an antimicrobial RiPP produced by *Lactococcus lactis*. Their diversity and applications continue to be the subject of ongoing research.                                                                                                                                                                                                        | **Nisin**             |
+| **Saccharides**                                                   | Saccharides produced in bacterial secondary metabolism are molecules synthesized by various mechanisms and then undergo subsequent enzymatic modifications based on the addition of carbohydrates. Two notable examples are Kanamycin, an aminoglycoside produced by *Streptomyces kanamyceticus*, used to treat bacterial infections, and Streptomycin, another aminoglycoside produced by *Streptomyces griseus*, which was one of the first antibiotics used to treat tuberculosis. Although their use has decreased due to bacterial resistance, they remain important in some cases.                                                                                                                                                                                                                         | **Kanamycin**         |
+| **Terpenes**                                                      | Traditionally, terpenes have been considered derivatives of 2-methyl-butadiene, better known as isoprene. Although they have been related to isoprene, terpenes do not directly derive from isoprene, as it has never been found as a natural product. The true precursor of terpenes is mevalonic acid, which comes from acetyl coenzyme A. Terpenes originate through the enzymatic polymerization of two or more isoprene units, assembled and modified in many different ways. Most terpenes have multicentric structures that differ not only in functional group but also in their basic carbon skeleton. These compounds are the main constituent of the essential oils of some plants and flowers, such as lemon and orange trees. They serve various functions in plants, such as being part of chlorophyll, carotenoid pigments, gibberellin and abscisic acid hormones, and increasing the fixation of proteins to cell membranes through isoprenylation. Additionally, terpenes are used in traditional medicine, aromatherapy, and as potential pharmacological agents. Two notable examples of terpenes are limonene, present in citrus peels and used in perfumery and cleaning products, and hopanoids, pentacyclic compounds similar to sterols, whose main function is to confer rigidity to the plasma membrane in prokaryotes. | **Diplopterol**        |
+| **Alkaloids**                                                     | Alkaloids are a class of natural, basic organic compounds that contain at least one nitrogen atom. They are mainly derived from amino acids and are characterized by their water solubility in acidic pH and solubility in organic solvents at alkaline pH. These compounds are found in various organisms, such as plants, fungi, and bacteria. Alkaloids have a wide range of pharmacological activities, such as Quinine, used against malaria, and Ephedrine, a bronchodilator. Additionally, some alkaloids, such as BE-54017, have an unusual structure, as it presents an indenotryptoline skeleton, rarely observed in other bis-indoles; however, its specific application is not well documented.                                                                                                                                                                          | **BE-54017**           |
+
 
 ## Genome mining aims to find BGCs
 Natural products are encoded in [Biosynthetic Gene Clusters](https://en.wikipedia.org/wiki/Metabolic_gene_cluster