A. PENGERTIAN PROTEIN - PROTEIN

  

PROTEIN

PROTEIN A.

  A. PENGERTIAN PENGERTIAN PROTEIN PROTEIN PROTEIN BERASAL DARI BAHASA YUNANI PROTEIN BERASAL DARI BAHASA YUNANI “PROTOS”

  “PROTOS” THAT MEAN “THE PRIME IMPORTANCE”

  THAT MEAN “THE PRIME IMPORTANCE” ARTINYA : “TERUTAMA” ATAU “PENTING”

  ARTINYA : “TERUTAMA” ATAU “PENTING”

  G. MULDER MENEMUKAN BAHWA MENEMUKAN BAHWA SENYAWA INI DITEMUKAN PADA SEMUA SENYAWA INI DITEMUKAN PADA SEMUA ORGANISME HIDUP BAIK PADA TUMBUHAN ORGANISME HIDUP BAIK PADA TUMBUHAN

G. MULDER

MAUPUN HEWAN, MERUPAKAN KOMPONEN

  TERBESAR DALAM JARINGAN TUMBUHAN DAN TERBESAR DALAM JARINGAN TUMBUHAN DAN TUBUH HEWAN TUBUH HEWAN

  A. PENGERTIAN

  A. PENGERTIAN 

  PROTEIN MERUPAKAN SENYAWA POLIPEPTIDA PROTEIN MERUPAKAN SENYAWA POLIPEPTIDA 

  SETIAP PEPTIDA TERSUSUN ATAS ASAM SETIAP PEPTIDA TERSUSUN ATAS ASAM AMINO SEBAGAI KOMPONEN TERKECIL AMINO SEBAGAI KOMPONEN TERKECIL 

  UNSUR PENYUSUNNYA : C,H,O,N UNSUR PENYUSUNNYA : C,H,O,N B. ASAM AMINO

  B. ASAM AMINO ►

  ASAM AMINO ADALAH SENYAWA YANG ASAM AMINO ADALAH SENYAWA YANG TERSUSUN ATAS GUGUS TERSUSUN ATAS GUGUS

KARBOKSIL (COOH)

  DAN DAN

GUGUS AMIN (NH2)

  ► STRUKTUR :

  STRUKTUR : H H N N C C C C OH OH H H R O O H H

  C N O O C H H H H H C N O O C C H H H H H H H

  Glycine The simplest amino acid

  The side group

  Structure of Amino Acid

CONDENSATION OF AMINO ACID

  HOH water

• + Amino acid Amino acid Dipeptida

  An OH group from the acid end of A peptida bond (highlighted in one amino acid and an H atom red) forms between the two from the amino acid group of amino acids, creating a peptide another join to form a molecule of water

  JENIS ASAM AMINO JENIS ASAM AMINO 1.

  1. ASAM AMINO ESENSIAL ( ASAM AMINO ESENSIAL (

  INDISPENSABLE AMINO ACID)

  INDISPENSABLE AMINO ACID) ASAM AMINO YANG TIDAK DAPAT DISINTESIS ASAM AMINO YANG TIDAK DAPAT DISINTESIS OLEH TUBUH, HARUS DIPEROLEH DARI LUAR

  OLEH TUBUH, HARUS DIPEROLEH DARI LUAR (MAKANAN)

  (MAKANAN)

  2. ASAM AMINO NON ESENSIAL (

  2. ASAM AMINO NON ESENSIAL ( DISPENSABLE AMINO DISPENSABLE AMINO

  ACID) ACID)

  ASAM AMINO YANG DAPAT DISINTESIS DI DALAM ASAM AMINO YANG DAPAT DISINTESIS DI DALAM TUBUH, DARI SUPLAI NITROGEN

  TUBUH, DARI SUPLAI NITROGEN

  3. ASAM AMINO SEMI ESENSIAL (

  3. ASAM AMINO SEMI ESENSIAL ( CONDITIONALLY CONDITIONALLY

  ESSENSIAL) ESSENSIAL)

  

ASAM AMINO YANG PADA KONDISI TERTENTU TIDAK

ASAM AMINO YANG PADA KONDISI TERTENTU TIDAK

DAPAT DIBENTUK OLEH TUBUH DAPAT DIBENTUK OLEH TUBUH

  JENIS ASAM AMINO JENIS ASAM AMINO ESENSIAL NON ESENSIAL SEMI ESENSIAL Histidin Alanin Lisin Arginin Arginin

  Leusin Asparagin Isoleusin Asam aspartat Methionin Asam Glutamat Valin Glutamin Glutamin

  Threonin Glisin Venilalanin Serin Triptofan Prolin

  Sistein Sistein C. FUNGSI 1. SUMBER ENERGI 2. MEMBENTUK STRUKTUR SEL 3. MEMBENTUK SISTEM PERTAHANAN TUBUH 4. MEMBENTUK SENYAWA TUBUH YANG ESENSIAL 5. KESEIMBANGAN ASAM BASA 6. KESEIMBANGAN CAIRAN TUBUH 7. TRANSPOR ZAT GIZI

C. FUNGSI

  1. SUMBER ENERGI

  1. SUMBER ENERGI ►

  PROTEIN DIGUNAKAN SEBAGAI PROTEIN DIGUNAKAN SEBAGAI

SUMBER ENERGI BILA SUPLAI

SUMBER ENERGI BILA SUPLAI

KARBOHIDRAT DAN LEMAK KARBOHIDRAT DAN LEMAK KURANG KURANG ►

  KARBOHIDRAT DAN LEMAK KARBOHIDRAT DAN LEMAK ADALAH ADALAH “PROTEIN-SPARING

  “PROTEIN-SPARING ” ”

  They spare amino acids from being They spare amino acids from being burned for energy and allow them burned for energy and allow them

to be used for protein synthesis

to be used for protein synthesis

  2. MEMBENTUK STRUKTUR SEL

  2. MEMBENTUK STRUKTUR SEL ►

  SEL TERSUSUN ATAS PROTEIN SEL TERSUSUN ATAS PROTEIN ►

  FUNGSI PERTUMBUHAN DAN FUNGSI PERTUMBUHAN DAN PEMELIHARAAN PEMELIHARAAN ►

  FUNGSI KOLAGEN YAITU SUATU FUNGSI KOLAGEN YAITU SUATU PROTEIN FIBROUSA DI DALAM TUBUH PROTEIN FIBROUSA DI DALAM TUBUH YANG MEERUPAKAN KOMPONEN YANG MEERUPAKAN KOMPONEN JARINGAN IKAT (

  JARINGAN IKAT ( CONNECTIVE TISSUE CONNECTIVE TISSUE

  ) ) STRUCTURAL PROTEIN STRUCTURAL PROTEIN PROTEIN PROVIDE STRUCTURE TO ALL CELLS INCLUDING HAIR, NAILS, SKIN, AND BONE MOTOR PROTEIN : PROTEIN THAT TURN ENERGY

INTO MECHANICAL WORK. MOTOR PROTEIN ACTIVE IN PROCESSES SUCH AS DIVIDING CELLS, CONTRACTING MUSCLE, SWIMMING SPERM

  3. SISTEM PERTAHANAN TUBUH

  3. SISTEM PERTAHANAN TUBUH ►

  PROTEIN MEMBENTUK ANTIBODY YANG BERTANGGUNG JAWAB UNTUK MELAWAN INFEKSI

DAN BENDA ASING YANG MASUK DALAM TUBUH

►

  ANTIBODY : PROTEIN YANG DIHASILKAN OLEH B

LIMFOSIT SEBAGAI RESPON ADANYA ANTIGEN

(PROTEIN PADA VIRUS ATAU BAKTERI)

  ►

  IMUNOGLOBULIN (Ig A, Ig E, Ig M) ADALAH PROTEIN

  4. KESEIMBANGAN CAIRAN TUBUH

  4. KESEIMBANGAN CAIRAN TUBUH ►

  PROTEIN DARAH DAPAT MENGHASILKAN TEKANAN ONKOTIK, YAITU TEKANAN UNTUK MEMPERTAHANKAN AGAR CAIRAN

TUBUH TETAP BERADA PADA KOMPARTEMENNYA

  ► CAIRAN : - INTRASEL : DI DALAM SEL

• EKSTRASEL : a. INTERSELULER

B. INTRAVASKULAR

  ► DEFISIENSI PROTEIN DI DALAM DARAH AKAN MENYEBABKAN ODEMA KARENA TEKANAN ONKOTIK YANG DIHASILKAN OLEH PROTEIN TIDAK MAMPU MEMPERTAHANKAN CAIRAN UNTUK TETAP BERADA DI DALAM KOMPARTEMEN, SEHINGGA CAIRAN AKAN KELUAR---- ODEMA

  Tekanan onkotik Tekanan onkotik

  Tekanan darah yang Protein darah akan dihasilkan jandtung menarik cairan kedalam

  (tek. Hidrostatik

  5. MENGATUR ASAM BASA

  5. MENGATUR ASAM BASA ►

  PROTEIN DARAH DAPAT BERPERAN SEBAGAI BUFER ►

  PH DARAH DITENTUKAN OLEH KONSENTRASI ION HIDROGEN ►

  SEMAKIN TINGGI KONSENTRASI ION H SEMAKIN RENDAH PH (SEMAKIN ASAM) ►

  ASAM : PH < 7

  

6. MEMBENTUK SENYAWA TUBUH ESENSIAL

  

6. MEMBENTUK SENYAWA TUBUH ESENSIAL

►

  HORMON HORMON SUATU SENYAWA YANG DIHASILKAN OLEH TUBUH SUATU SENYAWA YANG DIHASILKAN OLEH TUBUH TERSUSUN ATAS PROTEIN UNTUK FUNGSI TERSUSUN ATAS PROTEIN UNTUK FUNGSI REGULATOR REGULATOR ►

  ENZIM ENZIM

ADALAH PROTEIN YANG MENGKATALIS REAKSI

ADALAH PROTEIN YANG MENGKATALIS REAKSI

KIMIA DI DALAM TUBUH KIMIA DI DALAM TUBUH ►

  HEMOGLOBIN HEMOGLOBIN KOMPONEN DARAH YANG TERSUSUN ATAS PROTEIN KOMPONEN DARAH YANG TERSUSUN ATAS PROTEIN DAN ZAT BESI DAN ZAT BESI

  

Human Insulin

  Human insulin is relatively small protein that consist of 51 amino acid in two short Polypeptide chains. Two brigdes link he two chains. A third bridge spans a section within the short chain. Known as disulfde bridges, these link involve the amino acid Cystein (Cys), whose side group contains sulfur (S). Cystein connect to each other

  7. TRANSPOR ZAT GIZI

  7. TRANSPOR ZAT GIZI ►

  

PROTEIN DI DALAM DARAH DAPAT

BERPERAN PENGANGKUT ZAT GIZI LAINNYA ►

  CONTOH : RETINOL BINDING- PROTEIN (RBP ) -

• TRANSFERIN
• TRANSF>LIPOPROTEIN
• LIPOPROTEIN

  D. DIGESTION AND ABSORPTION

  D. DIGESTION AND ABSORPTION Digestion is facilitated mostly by the Digestion is facilitated mostly by the stomach’s acid and enzymes, wich first stomach’s acid and enzymes, wich first denature dietary protein, then cleave denature dietary protein, then cleave them into smaller polypeptides and them into smaller polypeptides and some amino acid. some amino acid.

  Pancreatic an dintestinal enzymes split Pancreatic an dintestinal enzymes split this poly peptides further to oligo-, this poly peptides further to oligo-, tri-,and dipeptides, and then split most tri-,and dipeptides, and then split most of these to single amino acid. of these to single amino acid.

  Then carries in the membranes of Then carries in the membranes of intestinal cells transport the amino acid intestinal cells transport the amino acid into the cells, where they are releases into the cells, where they are releases into the bloodstream into the bloodstream

  What happen in each organd What happen in each organd ^{MOUTH Salivar y glands gallblader liver esophagus stomach pancreas Pancreatic duct Small intestine} PENCERNAAN PROTEIN PENCERNAAN PROTEIN MULUT : BELUM TERJADI PENCERNAAN

  MULUT : BELUM TERJADI PENCERNAAN PEPSIN

  PEPTIDA LAMBUNG : PROTEIN

  LAMBUNG : PROTEIN

HCL PANKREATIK PROTEASE PEPTIDASE

  USUS HALUS : PEPTIDA ALKALI

  PENCERNAAN PENCERNAAN DI LAMBUNG DI LAMBUNG ►

  Terjadi denaturasi protein oleh HCl, sehingga protein Terjadi denaturasi protein oleh HCl, sehingga protein mudah dipecah oleh enzim mudah dipecah oleh enzim

  ►

Dinding lambung menghasilkan pro-enzim pepsinogen,

  

Dinding lambung menghasilkan pro-enzim pepsinogen,

yang diaktifkan oleh HCl menjadi enzim pepsin yang diaktifkan oleh HCl menjadi enzim pepsin

  ► Pepsin sangat aktif pada pH 2,5 dan inactif pada pH >5

  Pepsin sangat aktif pada pH 2,5 dan inactif pada pH >5 ►

  Sekresi cairan lambung pH 0,8 dan bila bercampur dengan Sekresi cairan lambung pH 0,8 dan bila bercampur dengan

makanan maka pH menjadi 2-2,5 menjadi pH yang ideal

makanan maka pH menjadi 2-2,5 menjadi pH yang ideal

untuk mengaktifkan pepsin untuk mengaktifkan pepsin

  PENCERNAAN PENCERNAAN DI USUS HALUS DI USUS HALUS ►

  Pemecahan protein terjadi secara efektif di usus Pemecahan protein terjadi secara efektif di usus halus halus

  ► Dinding usus dan pankreas menghasilkan pro-

  Dinding usus dan pankreas menghasilkan pro- enzim tripsinogen dan kimotripsinogen sebagai enzim tripsinogen dan kimotripsinogen sebagai respon masuknya protein di dalam usus, yang respon masuknya protein di dalam usus, yang berubah menjadi enzim tripsin dan kimotripsin berubah menjadi enzim tripsin dan kimotripsin karena suasana alkali karena suasana alkali

  ► Enzim lainnya adalah peptidase memecah

  Enzim lainnya adalah peptidase memecah E. METABOLISME PROTEIN

  E. METABOLISME PROTEIN ►

DALAM KONDISI NORMAL, HANYA HANYA

  

15% PROTEIN DI DALAM TUBUH YANG

15% PROTEIN DI DALAM TUBUH YANG

  DIUBAH MENJADI ENERGI DIUBAH MENJADI ENERGI ►

  PROTEIN DI DALAM TUBUH MENGALAMI

PROTEIN DI DALAM TUBUH MENGALAMI

“TURN OVER”

  “TURN OVER”

  METABOLISM

METABOLISM

The sum total of all the chamical reactions

  The sum total of all the chamical reactions that go on in living cells that go on in living cells

  ► Anabolism : reaction in which small molecules

  Anabolism : reaction in which small molecules are put together to build larger one. are put together to build larger one.

  Anabolic reactions require energy Anabolic reactions require energy

  ► Catabolism : reactions in which large

  Catabolism : reactions in which large molecules are broken down to smaller one. molecules are broken down to smaller one.

  Catabolic reaction release energy Catabolic reaction release energy

  

PROTEIN SYNTHESIS

PROTEIN SYNTHESIS

►

  Protein can be synthesized in the body cell Protein can be synthesized in the body cell

  (ribosome) (ribosome)

  ► Each human being is unique because of small

  Each human being is unique because of small

differences in the body’s proteins., which in

differences in the body’s proteins., which in

turn, are determined by genes. turn, are determined by genes.

  ►

When a cell makes a protein, it’s called the

  When a cell makes a protein, it’s called the

gene for that protein has been “expressed.

gene for that protein has been “expressed.

  

Cells can regulate gene expression to make

Cells can regulate gene expression to make

the type of protein.

  

PROTEIN TURN OVER & AMINO ACID POOL

PROTEIN TURN OVER & AMINO ACID POOL

  Protein turn over : Protein turn over : ►

  Whitin each cell, protein are continually Whitin each cell, protein are continually being made and broken being made and broken

  ► When protein break down, they free amino

  When protein break down, they free amino acid acid

  ► These amino acid mix with amino acid from

  These amino acid mix with amino acid from

dietary protein form an “amino acid pool”

dietary protein form an “amino acid pool”

within the cells and circulating blood within the cells and circulating blood

  

NITROGEN BALANCE

NITROGEN BALANCE

►

  In healthy adults, protein synthesis balance In healthy adults, protein synthesis balance with degradation, and protein intake from foof

with degradation, and protein intake from foof

balances with nitrogen excretion in the urine,

balances with nitrogen excretion in the urine,

feces and sweat. feces and sweat.

  ►

Nitrogen status is positive in growing infants,

  

Nitrogen status is positive in growing infants,

children, adolescents, pregnant women children, adolescents, pregnant women

  ►

Nitrogen status is negative in people who are

  

Nitrogen status is negative in people who are

starving or suffering other severe stresses such starving or suffering other severe stresses such as burn, injuries, infections, fever as burn, injuries, infections, fever

JALUR METABOLISME PROTEIN

  PROTEIN KARBOHIDRAT LEMAK ASAM AMINO GLUKOSA GLISEROL ASAM LEMAK

  PIRUVAT

  ACETYL Co A

TCA CYCLE

  “TURN OVER PROTEIN”

  Pemecahan AA

  DIETARY

  Dari sell

  Degradasi PROTEIN protein

  BODY PROTEIN

ASAM AMINO

  Sintensis protein POOL AA DLM SEL

  Sintesis senyawa Non protein

  HATI : Kel. AA

  Asam Lemak

  Carbon Urea

  Glukosa METABOLISME PROTEIN METABOLISME PROTEIN PROSES METABOLISME PROTEIN ADA 2 MACAM :

  PROSES METABOLISME PROTEIN ADA 2 MACAM :

  1. PROSES TRANSAMINASI

  1. PROSES TRANSAMINASI

  2. PROSES DEAMINASI

  2. PROSES DEAMINASI ►

  TRANSAMINASI : TRANSAMINASI :

  

PROSES PEMINDAHAN GUGUS AMIN DARI SATU ASAM

PROSES PEMINDAHAN GUGUS AMIN DARI SATU ASAM AMINO UNTUK MEMBENTUK ASAM AMINO BARU AMINO UNTUK MEMBENTUK ASAM AMINO BARU CONTOH : PEMBENTUKAN SISTIN DARI METIONIN

  CONTOH : PEMBENTUKAN SISTIN DARI METIONIN ►

  DEAMINASI DEAMINASI

PROSES PENGHILANGAN GUGUS AMIN SEHINGGA AKAN

PROSES PENGHILANGAN GUGUS AMIN SEHINGGA AKAN

MEMBENTUK SENYAWA BARU MEMBENTUK SENYAWA BARU

  

DEAMINATION

DEAMINATION

►

  When amino acid are broken down (as occurs When amino acid are broken down (as occurs when they are used for energy), they are first when they are used for energy), they are first

deaminated, stripped of their amino groups.

deaminated, stripped of their amino groups.

  ► Deamination produce ammonia, which the

  Deamination produce ammonia, which the cells release into the bloodstream. cells release into the bloodstream.

  ► The liver pick up the ammonia, converts it

  The liver pick up the ammonia, converts it into urea (a less toxic compound), and into urea (a less toxic compound), and returns urea into the blood. returns urea into the blood.

  ► The production of urea increase as dietary

  The production of urea increase as dietary protein increase (max 250 g/day) protein increase (max 250 g/day)

  ► Two products result from deamination :

  Two products result from deamination : 1.

  1.

  α α keto acid (the carbon structure without keto acid (the carbon structure without amino group) amino group)

  2. Ammonia (NH3), a toxic compound

  2. Ammonia (NH3), a toxic compound ►

  Most amino acids can be used to Most amino acids can be used to synthesize glucose from pyruvate, they synthesize glucose from pyruvate, they are called a glucogenic amino acid are called a glucogenic amino acid

  ►

Some amino acids are converted directly

  

Some amino acids are converted directly

to acetyl CoA, they called ketogenic amino to acetyl CoA, they called ketogenic amino acid acid

AMINO ACID ENTER THE ENERGY PATHWAY

  Glucogenic Amino acids ^NH2 _NH2

  Piruvate Acetyl CoA

  TCA Ketogenic Amino acids ^NH2

  Glucogenic ^{NH2 CoA Coenzyme}

  Coenzyme ^H+ _E-

  To electron Transport chain

  CO2 TRANSAMINATION

TRANSAMINATION

►

  

The transfer of an amino group from one

The transfer of an amino group from one

amino acid to keto acid, producing a new

amino acid to keto acid, producing a new

non essential amino acid and a new keto

non essential amino acid and a new keto

acid acid

  ► Through many such transamination

  Through many such transamination reactions, involving many different keto reactions, involving many different keto acids, the liver cells can synthesize the non acids, the liver cells can synthesize the non essential amino acids essential amino acids

  C O COOH Side group

  C H NH2 Side group

• +

  C H NH2

  COOH

• Keto acid A Amino acid B

  C O Side group

  Side group

  TRANSAMINATION

UREA EXCRETION

  Blood stream

  The liver and kidneys both play a role in _{+ Amonia CO2 (NH3)} Disposing of excess nitrogen.

  Person with liver disease has high blood ammonia

  Liver _Urea

  Person with kidney disease has high blood _Urea urea

  Blood stream _Kidney Urea