G.N. Ramachandran Discovery


G.N Ramachandran:

 G.N. RAMACHANDRAN, an outstanding figure in the field of protein structure, was the founder of the ' Madras school' of conformational analysis  of biopolymers. His discovery  of the triple helical structure of collagen published in Natire in 1954  and his analysis of the allowed conformations of proteins through the use of the ' Ramachandran plot' rank among the most outstanding contributions in structural biology.He was born on October 8, 1922, in a small town, not far from Cochin on the southwestern coast of India. His father was a professor influence in shaping Ramachandran's interest in mathematics. After completing his school years, Ramachandran  graduated in 1942 as the top _ ranking student in the B.Sc. ( Honors) Physics course of the University of Madras. He received a Ph.D. from Cambridge University in 1949. While at Cambridge , Ramachandran met Linus  Pauling and was deeply influenced by his publications on models of  the œ_ helix and ß_ sheet structures  that directed  his attention to solving the structure of collagen.He passed away at the age of 78, on April 7, 2001.


Ramachandran was born in the town of Ernakulam, Kingdom of Cochin, India to a Tamil Brahmin  family.He completed his BSc honours in Physics from St Joseph's College, Tiruchirappalli in 1939. He joined the Indian Institute of science, Bangalore in 1942 in the Electrical Engineering Department. Quickly realising his interest in physics, he switched to the Department of Physics to complete his master's and doctoral thesis under the supervision of Nobel laureate  Sir C.V. Raman. In 1942, he received a master's degree in  physics from Madras University with his thesis submitted from Bangalore (he did not attend any Madras college at that time). He subsequently received his  D.Sc.degree in 1947. Here he mostly studied  crystal physics  and crystal optics . During his studies he created an X-ray focusing mirror for the X_ ray microscope. The resulting field of crystal topography is used extensively in studies involving  crystal growth and solid state reactivity .


Ramachandran then spent two years (1947–1949) at the Cavendish Laboratory  in Cambridge,where he earned his PhD for 'studies on X_ray diffuse scattering and its application to determination of elastic constants' under the direction of Professor William Alfred Wooster, popularly known as W.A. Wooster, a leading crystallography expert in the world. 

chromatography that, depending on the particular combination of packing material and solvent can incorporate the principles of partition, ion_ exchange, exclusion or affinity  chromatography.

(g) Gas chromatography : It is a special  form of column chromatography in which a gas is used as the mobile phase ( instead of  a liquid) and either a liquid  or a solid is used as the stationary phase. When liquid is used as the stationary phase, the technique is called gas_ liquid chromatography ( GLC).When stationary phase is solid, it is called gas_ solid chromatography. The gas generally used are nitrogen, carbondioxide, helium or argon.

Electrophoresis 

Molecules are separated from one another in electrical potential gradients on the basis of differences in their net charges, sizes and shapes. The  method is employed most often for the separation of different  proteins

Spectrophotometry 

This technique is used to find the qualitative and quantitative analysis of mixtures of molecules in solution. The  solution containing  the  dissolved  chemicals is exposed to selected wavelength and the absorption spectrum recorded. It is compared to standard absorption spectra of different molecules to know composition of solution. 

Autoradiography 

Cells use many atoms of substances to synthesize their molecules. Some of these can be made radioactive and these radioactive substances emit rays which can form images in photographic emulsion. By studying successive stages of the cells by autoradiography one can follow the fate of molecules. This helps one to understand  many chemical events in succession. Various  radio isotopes used are_ H³, C¹⁴, P³², S³⁵.


X_ ray Crystallography (Bragg, 1913) :

It is the process of determination  of molecular structure by passing X_ ray through the substance present in  a crystalline state. It can give important information about the arrangement of atoms in the molecule of substance such as enzymes. X_ ray microscopy was developed by Kirtpatric Watson and Crick ( 1953) confirmed the structure of DNA from X_ ray diffraction by Astbury and Franklin ( 1953).

G.N Ramachandran contribution physics? 


G.N. Ramachandran, also known as Gopalasamudram Narayana Iyer Ramachandran, was an Indian physicist and biophysicist. Although he is best known for his contributions to the field of structural biology and biochemistry, his work had significant implications for physics as well.

Ramachandran made several important contributions to the understanding of protein structure and the relationship between protein structure and function. He is particularly renowned for his development of the Ramachandran plot, which is a graph that shows the allowed regions of phi and psi angles, defining the main-chain conformation of amino acids in a protein. This plot became an invaluable tool for protein structure analysis and prediction and has had a profound impact on the field of structural biology.

Ramachandran's work on the structure and conformation of polypeptides helped elucidate the principles underlying protein folding and provided insights into the stability and dynamics of protein molecules. His research played a crucial role in the development of the field of protein structure determination and contributed to our understanding of the relationship between protein structure and function.

Overall, Ramachandran's contributions to the field of structural biology have had a profound impact on both biology and physics, and his work continues to be influential in various scientific disciplines.

What is G.N Ramachandran plot?


The G.N. Ramachandran plot is a graphical representation of the dihedral angles of amino acid residues in a protein. It plots the phi and psi angles on the x and y axes, respectively. The plot helps in analyzing the conformation of protein structures and identifying energetically favorable or unfavorable regions. The Ramachandran plot is named after its creator, Gopalasamudram Narayana Ramachandran, an Indian physicist and biophysicist.

Summary of G.N Ramachandran's Career 

Gopalasamudram Narayana Ramachandran 

Born on October 8,1922 

Father : G.R. Narayana Iyer 

Mother : Lakshmi Ammal

Education 

1939-42 : BSc(Hons) Physics, St. Joseph’s College, Trichy 

1942_ 44: MSc Physics, India Institute, of Science ( HSc, Bangalore
 
1944_ 47 : DSc Physcis, HSc ( Under the supervision of Prof . C.V.Raman) 

1947_ 49: PhD Crystallography, Cavendish laboratory, University of Cambridge, England 

Professional occupations

1949_ 52: Assistant Professor of Physics, Hsc Bangalore

 1952_ 70 : Professor & Heaf of Deptt. of Physics, University of Madras

 1971 _ 78: Professor & Head, Molecular Biophysics Unit, IISc Bangalore

 1978_ 81: Institute Professor, Mathematical Philosophy, IISc, Banglore

 1981_ 84: CSIR Distinguishef Scientist

 1984_ 89: INSA Albert Einstein Professor, Mathematical Phpsophy Group, IISc Bangalore.

 He also  held the following assignments: Director , Centre for Advanced Study in Biophysics & Crystallography, University of Madras ( 1962_ 70);Jawaharial Nehru Fellowship ( 1967_ 71); Part _ time professor of Biophysics, University of Chicago, Chicago. 

Fellow of the Indian National Science Academy ( FNA) .

Fellow of  the Royal Society of Arts, London ( FRSA)  

Follow of the Royal Society, London ( FRS) 

 Founder Member of the Third World Academy of Sciences.

Member, Council of International Union of pure & applied Biophysics ( IVPAB) ( 1969_ 74)

Member, various Sub_ commissions of the commission on Biochemical Nomenclature of the IUPAC_ IUB( 1066_79)

 Professor Ramachandran was a member of editorial boards of a number of national and international journals. 

Membership in professional organisaitons/bodies ( all are not included) 

Important research Contributions: 

His most important contributions were:_ 

Discovery of the triple helical structure of the connective tissue protein called collagen.

_ ' The Ramachandran phi_ psi Plot'which has become a standard description of protein structure. 


– Development of the theory of image reconstruction from shadawgraphs (such as X-radiograms) using the Convolution Technique. 

-Ramachandran received a number of national/international awards. He died on April 07, 2001.

When was Ramachandran plot discovered?


The Ramachandran plot was discovered or introduced by G.N. Ramachandran in the year 1963.

G.N Ramachandran Nobel prize 


G.N. Ramachandran, also known as Gobindarajan Ramachandran, did not receive a Nobel Prize during his lifetime. However, his contributions to the field of structural biology, particularly his work on the Ramachandran plot and understanding protein structures, were highly significant and influential. He received several other prestigious awards and honors for his groundbreaking research.


G.N Ramachandran inventions 



G.N. Ramachandran is a renowned scientist and mathematician who made significant contributions to the field of structural biology. While he is known for his groundbreaking theories and discoveries, he did not invent specific physical devices or technologies. Ramachandran's most notable contribution is the development of the Ramachandran plot, a graphical representation of the allowed and forbidden regions of protein backbone dihedral angles. This plot is widely used in the field of protein structure determination and has been instrumental in understanding the conformational space of proteins. Ramachandran's work has laid the foundation for the field of bioinformatics and has had a profound impact on the study of proteins and their functions.


Cell : Structure And Functions 

Biology is the study of living organisms. The detailed description of their form and appearance only brought out their diversity. It is the cell theory that emphasizes the unit underlying this diversity  of forms, i.e., the cellular organisation of all life forms. A description of cell structure and cell growth by division is given in the comprising this unit. Cell theory also created a sense of mystery around living  phenomenon, i.e., physiological and behavioral processes. This mystery was the requirement of integrity of cellular orgaisation for living phenomenon to be demonstrated or observed. In studying and understanding the physiological and behavioral processes, one can take a physico _ chemical approach and use cell_ free  systems to investigate. This approach enables us to describe the various processes in molecular terms. The approach is established by various processes in molecular terms. The approach is established by analysis of living tissues for elements and compounds. It will tell us  what types of organic compounds are present  in living organisms. In the next stage, one can ask the question: What are these compounds doing  inside a cell? And, in what way they carry out gross physiological processes like digestion,  excretion, memory, defense, recognition, etc. In other words we answer the question, what is the molecular basis of all physiological processes? It can also explain the abnormal processes that occur during any diseased condition. This physico_ chemical approach to study and understand living organisms is called ' Reductionist Biology'. The concepts and techniques of physics and chemistry  are applied to understand biology. This unit description of biomolecules is provided.

Cell: The Unit of life

 SUMMARY

All organisms are made of cells or aggregates of cells. Cells vary in their shape, size and activities/ functions. Based on the presence or absence of a membrane bound nucleus and other organelles, cells and hence organisms can be named as Eukaryotic or prokaryotic. 
 
 A typical eukaryotic cell consists of a cell membrane, nucleus and cytoplasm. Plant  cells have a cell wall outside the cell membrane.  The plasma membranes is selectively permeable and facilitates transport of several molecules. The endomembrane system includes ER,golgi complex,lysosomes and vacuoles. All the cell organelles perform different but specific functions. Centrosome and centriole form the basal body of cilia and flagella that facilitate locomotion. In animal  cells, centrioles also form spindle  apparatus during cell division . Nucleus contains nucleoli and chromatin network. It not only controls the activities of organelles  but also plays a major role in heredity. 

  Endoplasmic reticulum contains tubules or cisternae. They are of two types:  rough and smooth.  ER helps in the transport of substances, synthesis of proteins,  lipoproteins and  glycogen.  The  golgi  body is a membranous organelle composed of flattened sacs. The secretions of cells are packed in them and transported from the cell. Lysosomes are single membrane structures containing enzymes for digestion of all types  of macromolecules. Ribosomes are involved in protein synthesis. These occur freely in the cytoplasm or are associated with ER. Mitochondria help in oxidative phosphorylation and generation of adenosine triphosphate. They are bound  by double membrane; the outer membrane is  smooth and inner one folds into several cristae. Plastids are pigment containing  organelles found in plant cells only. In plant cells, chloroplasts are responsible for trapping light energy essential for photosynthesis. The grana, in the plastid, is the site of light energy reactions and the stroma of dark reactions. The green coloured plastids are chromoplasts, which may contain pigments like carotene and xanthophyll. The nucleus is  enclosed by nuclear envelope, a double membrane structure with nuclear pores. The inner membrane enclose the nucleoplasm and the chromatin material. Thus, cell is the structural and functional unit of life. 


Biomolecules: 

Although there is a bewildering  diversity of living organisms, their chemical composition and metabolic reactions appear to be remarkable similar. The elemental composition of living tissues and non_ living  matter appear also to be similar when analysed qualitatively. However, a closer examination reveals that the relative  abundance of carbon, hydrogen and oxygen is higher in living systems when compared to inanimate matter. The most abundant chemical in living  organisms is water. There are thousands of small  molecular weight ( <1000 Da ) biomolecules. Amino , monosaccharide and disaccharides sugars, fatty acids, glycerol,  nucleotides, nucleosides and nitrogen bases are some of the organic compounds seen in living organisms. There are 20 types of amino acids and 5 types of nucleotides. Fats and oils are glycerides in which fatty acids are esterified to glycerol. Phospholipids contains, in addition, a phosphorylated nitrogenous compound. 

Only three types of  macromolecules, i.e., proteins, nucleic acids and polysaccharides are found in living systems. Lipids, because of their association with membranes separate in the macromolecular fraction. Biomacromolecules are polymerase. They are made of building blocks which are different. Proteins are heteropolymers made of amino acids. Nucleic acids { RNA and DNA} are composed of nucleotides. Biomacromolecules have a hierarchy of structures _ primary, secondary,  tertiary and quaternary. Nucleic acids serve as genetic material. Polsaccharides are components of cell wall in plants, fungi and also of the exoskeleton of arthropods. They also are storage forms of energy ( e.g., starch and glycogen). Proteins serve a variety of cellular functions. Many of them are enzymes, some are antibodies, some are receptors, some are hormones and some others are structural proteins. Collagen is the most abundant protein in animal world and Ribulose bisphosphate Carboxylase _ Oxygenase ( RuBisCO) is the most abundant  protein in the whole of the biosphere. 

  Enzymes are proteins which catalyse biochemical reactions in the  cells. Ribozymes are nucleic acids with catalytic power. Proteinaceous enzymes exhibit substrate specificity, require optimum temperature and pH for maximal activity. They are denatured at high temperatures. Enzymes lower activation energy of reactions and enhance greatly  the rate of the reactions. Nucleic acids carry hereditary information and are passed on form parental generation to progeny.

Cell : Cycle and Cell Division 

According to the cell theory, cells arise from preexisting cells. The process by which this occurs is called cell division.Any sexually reproducing organisms starts its life cycle from a single_ celled zygote. Cell division does  not stop with the formation of the mature organism but continues throughout its life cycle. The stage throug which a cell passes from one division to the next is called the cell cycle. Cell cycle is divided into two phase called (i) Interphase _ a period of preparation for cell division, and (ii)Mitosis [M phase] _ the  actual period of cell  division. Interphase is further subdivided into normal metabolism. Most of the organelle duplication also occurs during this phase. S phase marks the phase of DNA replication and chromosome duplication. G2 phase is the period of cytoplasmic growth.Mitosis is also divided into four stages namely prophase, metaphase, anaphase and telophase.Chromosome condensation occurs during prophase. Simultaneously, the centrioles move to the opposite poles. The nuclear envelope and the nucleolus disappear and the spindle fibres start appearing. Metaphase is marked  by the alignment of chromosomes at the equtorial plate. During anaphase the centromeres divide and the chromatids start moving towards the two opposite poles. Once the chromatids reach the twi poles, the chromosomal elongation starts,nucleolus and the nuclear membrane reappear.This stage is called the telophase. Nuclear division is then followed by the cytoplasmic division and is called cytokinesis. Mitosis thus,is the equational division in which the chromosome number of the parent is conserved in the daughter cell.

 In contrast to mitosis, meiosis occurs in the diploid cells, which are destined to form gametes. It is called the reduction division since it reduces the chromosome number by half  while making the gametes. In sexual reproduction when the two gametes fuse the chromosomes number is restored to the  value in the parent. Meiosis is division into two phases__ meiosis I and Meiosis II. In the first  meiotic division the homologous chromosomes pair to form bivalents, and indergo crossing over. Meiosis I has a long prophase, which is divided further into five phases. These are leptotene, Zygotene,  Pachytene, Diplotene and diakinesis. During metaphase I the bivalents arrange on the equatorial plate. This is followed by anaphase I in which homologous chromosomes move to the opposite poles with both their chromatids. Each pole receives  half the chromosome number of the parent cell. In telophase I, the nuclear membrane and nucleolus reappear. Meiosis II is similar  to mitosis. During anaphasr II the sister chromatids separate. Thus at the end of meiosis four haploid  cells are formed. 
















































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