In life, living things require energy derived from metabolic processes. Metabolism occurs in all living things including microbial life. In
animals or plants in the high degree of enzyme for the metabolism
reatif provide stable, during the development of the individual changes
in the composition of the enzyme is indeed the case, but at the turn of
the change is very small environment.Metabolism is a series of chemical reactions that occur in living cells (Bibiana W. Lay, 1992 in Darkuni, 2001). There are two phases in the metabolism of the catabolism and anabolism. This
always occurs in the metabolism of living cells because the enzyme in
living cells are needed to help a variety of chemical reactions that
occur. A process of chemical reactions that occur can result in energy and may also require energy to assist the reaction.According
Darkuni (2001) when in a reaction producing energy is called exergonic
reactions, and if the course of a reaction to the energy required, these
reactions are called endergonic reactions. Metabolic activity includes the changes made to a series of sequential enzyme reaction. In brief, the activities of this process is called tansformasi substance. The
results of this activity will produce a simple nutrients such as
glucose, long chain fatty acids or aromatic compounds that can be used
as material for neosintetik process, the cell material according to
Anonimous (2008) the enzyme is influenced by several things: The concentration of enzyme The concentration of substrate pH temperatureEach enzyme works best at a particular pH and temperature. Very low temperatures to stop the enzyme activity but does not destroy it. Enzyme activity is regulated through two ways:Catalyst
control directly the genetic control of metabolic processes will
produce the metabolism of the function on the sub unit of the metabolism
of macromolecules that are useful for providing an early stage to
produce cell components and provides the energy generated from ATP by
ADP with phosphate. This energy is very important for the activities of other processes in the process only if the available energy berlagsung. Forms of Microbial Metabolism In Photosynthesis is the process of preparation or formation using light energy or photons. Source
of natural light is the sun's energy spectrum of infrared light
(invisible), red, orange, yellow, green, blue, indigo, violet and ultra
violet (not visible) (Anonymous, 2000). Most
Bacteria do not have chlorophyll, but there are also some species that
have photosynthetic pigments called bakterioklorofil. Bacterial
photosynthesis occurs in the same manner as in green plants, except
that the bacteria do not have the photosystem II for water photolysis. So as the water is never a source of reductant and oxygen was never formed as a product.
In bacterial photosynthetic reaction equation is as follows:n CO2 + 2n H2A (CH 2 O) n + n + 2n H2O Awhere: H2A = hydrogen donor (either H2S or organic acids)H2A in the above equation can be organika or inorganic substrates instead of H2O. According to Volk & Wheeler (1993) based on the pigment and the type of reductant used in photosynthesis (represented by H2A) photosynthetic bacteria are classified into three tribes:ChlorobiaceaeThese bacteria are also called as green sulfur bacteria. These organisms use several compounds containing sulfur or hydrogen gas as a reductant of photosynthesis. Typical formula for the photosynthesis of green sulfur bacteria is one among the following depending on the available reductant(CH 2 O represents carbohydrates are synthesized) CO2 + light 2H2S (CH 2 O) + + H2O + 2S 2S3CO2 · 5H2O + light 3 (CH 2 O) + Na2S2O3 3H2O 2CO2 + light 2 (CH 2 O) + H2SO4 Na2SO4 + CO2 + 2H2O light (CH2) + H2OChromaticeaeThese bacteria also called purple sulfur bacteria are different from the green sulfur bacteria is mainly due to these bacteria contain a number of carotenoid pigments of red and purple in his cell. These bacteria use photosynthesis same reductant used by green sulfur bacteria, purple sulfur bacteria that can perform the same reactions to the green sulfur bacteria.RhodospirillaceaeThese bacteria are also called as non-sulfur purple bacteria. In the morphology of these bacteria have in common with Chromaticeae but not able to use sulfur compounds as photosynthetic reductant. Two genera of this tribe is the most studied Rhodospirillum and Rhodopseudomonas. These organisms can use hydrogen or various organic compounds as a reductant. Here is one example:2CH3CHOHCH3 light CO2 + (CH 2 O) + H2O + 2CH3COCH3One important properties of photosynthetic bacteria that can not be met on the photosynthesis of green plants are photosynthetic bacteria that can only take place in a state devoid of oxygen. But some tribal members Rhodospirillaceae can grow without photosynthesis in a state if there is oxygen in the given medium is fertile enough to grow. Chlorophyll a little different bacteria with chlorophyll of green plants, light with a longer wavelength is absorbed by the bacteria rather than green plants.FotolitotrofBodies that use inorganic substances as an electron donor such as H2, NH3, or S is called the body of litotrof. Fotolitotrof bodies depends only on sunlight and inorganic compounds as electron donor for growth. In bacteria fotolitotrof hydrogen source is not the water, and oxygen was never produced dalamproses photosynthesis (Tarin, 1988). Fotosintesisnya reaction pattern can be written as follows:n CO2 + n H 2 -----------------> (CH 2 O) n + H2O + 2 n n SIn this synthesis is not O2 produced, but the sulfur (S) is stored for later daalm cells are removed and H2S meruapakan hydrogen donor.KemolitotrofSource of energy bodies are included in the group kemolitotrof depends on the results of oxidation reduction, and can use inorganic compounds as electron donor for growth.FotoorganotrofBodies that include fotorganotrof only depends on the energy of sunlight by using organic compounds as electron donor for growth. Sulfur bacteria mengabsorb organic materials from their environment as a source of hydrogen, but these metabolites can not be used directly as a nutrient. H2 obtained will berswenyawa dengna CO2 to produce carbohydrates.KemoorganotrofBodies that include this kemoorganotrof his life depends on the results of oxidation-reduction and organic compounds as electron donor for growth. Types of nutrients in this group different from other types of classes of nutrients, because nutrients in the body of one of those kemoorganotrof can take place in the dark but there must be oxygen. In this case the organic raw materials are directly absorbed and used as a nutrient.The formation process of ATP formation of ATP (Adenosine triphosphat) is the energy generated. The energy generated in the form of ATP. ATP is necessary to establish as many as 7-8 Kcal of energy and the addition of phosphate. Therefore, the formation of phosphate. Therefore, the formation of ATP is also called by the name of phosphorylation. General pattern of formation of ATP is described as follows: ADP + Pi ATP of 7-8 KcalThe process of phosphorylation of ADP (adenosine diphosphate) can occur through: photosynthetic phosphorylation, carried out by microbes that can make the process of photosyntheticsubstrate phosphorylation, carried out by microbes that do not have the ability to perform photosynthetic, primary source for obtaining the energy of the substrateoxidative phosphorylation, carried out by microbes that can not perform photosynthesis and do not require as our substrate for energy sources. This energy is obtained for the oxidation. ATP phosphorylation carried out to obtain because of the need for a compound that binds to high and the results obtained from the activation susbstrat. Activation of the enzyme is aided by the presence of the enzyme NAD and FAD. Krebs cyclePerfect for glucose catabolism compound that will produce CO2 and H2O occurs in 3 stages: glycolysis, Krebs cycle and electron transport or electron trsnsport system (ETS). Of pathways of glucose penguarian pyruvic acid will be produced which would then be oxidized via the Krebs cycle or TCA cycle (tricarboxylic acid Trikarbiksilad acid =). Also known by other names that the citric acid cycle as this cycle begins a series of citric acid. Krebs cycle is sebenarntya a main road on the generation of ATP in the business group aerobic microbes or bacteria, that is through phosphorylation of oxidation. If there is oxygen, the energy of pyruvic acid will be converted through anaerobic respiration. This process will lead to the loss of one molecule of carbon and the formation of CO2 and the enzyme NADH. In the Krebs cycle, citric acid (6C) is converted into acid by carbon oksaluasetat into 4 (4C). This process is carried out by oxidation and decarboxylation reactions. Electron transport system is also a respiratory chain, an electron pathway dihsilak use by metabolism primarily by aerobic metabolism. There are also some of the reactions used by anaerobic bacteria.NADH and FADH2 produced by aerobic respiration and also by the Krebs cycle are transported and transferred kemolekul carrier (carrier molecules) contained in the lipid membrane. Carrier molecule is composed of protein and non protein. Part of a flavoprotein and cytochrome protein. While the non-protein form of quinone in the form of coenzyme Q. Pengangukutan chain was started by the oxidation of NADH and followed by the reduction of FAD to FADH and ATP will be generated. The formation of ATP by oxidative phosphorylation carried out. At the end of this chain reaction rentetat elekron Alkan aseptor react with oxygen as the electron with the help of the enzyme cytochrome oxidase. Oxygen will react with hydrogen ions to form water. The series of reactions in this system can be described as a chain on each link in the chain will be skipped electrons. At each link in the chain, in particular the reaction to release energy so that energy can be used to produce ATP. Electron transport system takes place in the cell membrane prokaryotes.Hydrolysis of starch is a carbohydrate intake in type polysaccharide. Polysaccharides are macromolecules, polymers with several monosaccharides are connected by a glycosidic bond. Beerapa polysaccharides serve as material deposits or reserves which will be hydrolyzed when necessary to provide sugar to the cells (Campbell, 2002). The ability to use sugar or elements associated with different configurations of glucose is the result of the ability of organisms to convert substrate into intermediaries as a pathway to ferment glucose (Kusnani, 2003). Based on observations of bacterial metabolism, it appears that all the bacteria, either Escerichia coli, Bacillus subtilis, and Streptococcus aureus able to hydrolyze starch. Evidence that all these bacteria are able to hydrolyze starch is a clear or transparent areas contained in the growing colonies of bacteria (results of inoculation). Ability to hydrolyze starch into glucose, maltose, and dextrin as having amylase enzyme. Starch can not be directly used, so the bacteria must first hydrolyze starch into simple molecules into the cell (Kaiser, 2005). According Hadioetomo (1990), starch hydrolysis positive test function in bacteria is characterized by apparently clear area around the streaking bacterial growth. The existence of these clear areas and organisms caused eksoenzim hydrolyze starch in agar medium. According Schegel (1994), fungi or bacteria to produce α-amylase with starch so as to describe the vast eksoenzim amilolitik between microorganisms, including bacteria Bacillus macerans, Bacillus polimexa, and Bacillus subtilis. On the observations is known that Escerichia coli has the ability to hydrolyze starch in the highest because of the clear area around the colony indicated the most widely Escerichia coli than other bacteria. When viewed from the opinion Schegel possible number of cells inoculated Escerichia coli are more numerous in the medium. So the number of cells to metabolize more and more, and clearly demonstrated the most extensive in sight. In the test of the hydrolysis of starch iodine solution used in the final stage. Iodine is used as an indicator of starch, when the medium containing starch or starch iodine is given then it will appear blue. However, if starch or hydrolyzed starch was then the colors will be clear or translucent. Color clearly indicates that the starch or starch is hydrolyzed by eksoenzim in bacteria (Hadioetomo, 1990). According to Kaiser (2005) clear or translucent in color around the bacteria after adding iodine starch can not be caused by long react with iodine. In all three bacteria were observed, all of which can hydrolyze starch, indicating that these bacteria produce the enzyme α-amylase. Fat hydrolysis Based on observations and data analysis three Escerichia coli bacteria, Bacillus subtilis, and Streptococcus aureus can hydrolyze fats, and which has the highest capacity to hydrolyze fat is Streptococcus aureus. This is evident from the intensity shown in red beneath the growth of Streptococcus aureus bacteria. This indicates that the amount of lipase enzyme produced by this bacterium is greatest when compared to other bacteria. Ability of the enzyme lipase in the fat molecules break into fatty acids and glycerol, at most. S. aureus is a place to live normally live on the face and cause acne for patient generally is supporting evidence that S. aureus hydrolyzes the optimum in fat as an energy source for cell growth and development. According Gaman, et al (1981) fat is a mixture comprising trigleserida 1 glycerol molecule bonded to 3 fatty acid molecules. Fat has such properties: insoluble in water, when heated will be changes in the melting point, smoke point and flash point, as well as plastic and easily changing shape when under pressure, may develop rancidity, and the reaction with alkali to form soap and glycerol. Lipase enzyme can hydrolyze fats and break into 3 molecules of fatty acids and a glycerol molecule, a chemical reaction which shows hydrolysis are as follows:Hydrolysis of Proteins Based on observations and analysis of data on the medium plates Skim Milk Agar (SMA) which is used to identify bacteria that can menghidrolisa casein, three types of bacteria (Escerichia coli, Bacillus subtilis, and Streptococcus aureus) is able to hydrolyze the protein. The ability of bacteria hydrolyze proteins in a region indicated by the formation of clear / clear around the scratches (where the growth of bacteria inoculated). This is in accordance with the opinion Hadioetomo (1990) which states that a positive test is characterized by apparently clear area around the streaking organism growth. Of the three bacteria (Escerichia coli, Bacillus subtilis, and Streptococcus aureus) has an ability to hydrolyze different as indicated on the data of observations, data from observations in a sequence based on its ability to hydrolyze the protein from the highest to the lowest is Bacillus subtilis, Escerichia coli and S. aureus. Differences in the ability of protein memghidrolisis prosuksi eksoenzim possible due to a different protease enzymes. Bacillus subtilis is possible to have the ability to produce more proteases than Escerichia coli, and Streptococcus aureus. The other possibility of differences in the ability to hydrolyze proteins are bacterial cells of each type of medium was inoculated at the same time not affecting the result of hydrolysis of these proteins are characterized by differences in the number of colonies that grew on the medium. Differences in the number of bacterial cells on each type of bacteria can provide a real effect. The more the number of bacterial cells, the more cell metabolism, resulting in the clear area on the medium. Protein hydrolysis is due to enzymatic reactions. Bacteria are able to hydrolyze casein has eksoenzim, that promote the suspension (medium) would be a clear area around bakteripertumbuhan bacterial growth. Kaiser (2005) states that if the bacteria are able to hydrolyze casein has eksoenzim, then the suspension it became clear the area around the growth of bacteria. Protein is an important compound in the body of a living organism. Medium that is used to detect the hydrolysis of protein is made from skim milk mixed with agar and distilled water, which in the skim milk contains casein which will be hydrolyzed into peptides and amino acids.Bacteria do the hydrolysis of various proteins into single amino acids in order to use these amino acids for protein synthesis and other cellular molecules or as an energy source (Kaiser, 2005). In our observation, clear area formed around the bacterial growth, this is caused by casein which appear white in a colloidal suspension (SMA medium) was hydrolyzed to peptides and amino acids which results in energy used for growth and development of cell metabolism.
In bacterial photosynthetic reaction equation is as follows:n CO2 + 2n H2A (CH 2 O) n + n + 2n H2O Awhere: H2A = hydrogen donor (either H2S or organic acids)H2A in the above equation can be organika or inorganic substrates instead of H2O. According to Volk & Wheeler (1993) based on the pigment and the type of reductant used in photosynthesis (represented by H2A) photosynthetic bacteria are classified into three tribes:ChlorobiaceaeThese bacteria are also called as green sulfur bacteria. These organisms use several compounds containing sulfur or hydrogen gas as a reductant of photosynthesis. Typical formula for the photosynthesis of green sulfur bacteria is one among the following depending on the available reductant(CH 2 O represents carbohydrates are synthesized) CO2 + light 2H2S (CH 2 O) + + H2O + 2S 2S3CO2 · 5H2O + light 3 (CH 2 O) + Na2S2O3 3H2O 2CO2 + light 2 (CH 2 O) + H2SO4 Na2SO4 + CO2 + 2H2O light (CH2) + H2OChromaticeaeThese bacteria also called purple sulfur bacteria are different from the green sulfur bacteria is mainly due to these bacteria contain a number of carotenoid pigments of red and purple in his cell. These bacteria use photosynthesis same reductant used by green sulfur bacteria, purple sulfur bacteria that can perform the same reactions to the green sulfur bacteria.RhodospirillaceaeThese bacteria are also called as non-sulfur purple bacteria. In the morphology of these bacteria have in common with Chromaticeae but not able to use sulfur compounds as photosynthetic reductant. Two genera of this tribe is the most studied Rhodospirillum and Rhodopseudomonas. These organisms can use hydrogen or various organic compounds as a reductant. Here is one example:2CH3CHOHCH3 light CO2 + (CH 2 O) + H2O + 2CH3COCH3One important properties of photosynthetic bacteria that can not be met on the photosynthesis of green plants are photosynthetic bacteria that can only take place in a state devoid of oxygen. But some tribal members Rhodospirillaceae can grow without photosynthesis in a state if there is oxygen in the given medium is fertile enough to grow. Chlorophyll a little different bacteria with chlorophyll of green plants, light with a longer wavelength is absorbed by the bacteria rather than green plants.FotolitotrofBodies that use inorganic substances as an electron donor such as H2, NH3, or S is called the body of litotrof. Fotolitotrof bodies depends only on sunlight and inorganic compounds as electron donor for growth. In bacteria fotolitotrof hydrogen source is not the water, and oxygen was never produced dalamproses photosynthesis (Tarin, 1988). Fotosintesisnya reaction pattern can be written as follows:n CO2 + n H 2 -----------------> (CH 2 O) n + H2O + 2 n n SIn this synthesis is not O2 produced, but the sulfur (S) is stored for later daalm cells are removed and H2S meruapakan hydrogen donor.KemolitotrofSource of energy bodies are included in the group kemolitotrof depends on the results of oxidation reduction, and can use inorganic compounds as electron donor for growth.FotoorganotrofBodies that include fotorganotrof only depends on the energy of sunlight by using organic compounds as electron donor for growth. Sulfur bacteria mengabsorb organic materials from their environment as a source of hydrogen, but these metabolites can not be used directly as a nutrient. H2 obtained will berswenyawa dengna CO2 to produce carbohydrates.KemoorganotrofBodies that include this kemoorganotrof his life depends on the results of oxidation-reduction and organic compounds as electron donor for growth. Types of nutrients in this group different from other types of classes of nutrients, because nutrients in the body of one of those kemoorganotrof can take place in the dark but there must be oxygen. In this case the organic raw materials are directly absorbed and used as a nutrient.The formation process of ATP formation of ATP (Adenosine triphosphat) is the energy generated. The energy generated in the form of ATP. ATP is necessary to establish as many as 7-8 Kcal of energy and the addition of phosphate. Therefore, the formation of phosphate. Therefore, the formation of ATP is also called by the name of phosphorylation. General pattern of formation of ATP is described as follows: ADP + Pi ATP of 7-8 KcalThe process of phosphorylation of ADP (adenosine diphosphate) can occur through: photosynthetic phosphorylation, carried out by microbes that can make the process of photosyntheticsubstrate phosphorylation, carried out by microbes that do not have the ability to perform photosynthetic, primary source for obtaining the energy of the substrateoxidative phosphorylation, carried out by microbes that can not perform photosynthesis and do not require as our substrate for energy sources. This energy is obtained for the oxidation. ATP phosphorylation carried out to obtain because of the need for a compound that binds to high and the results obtained from the activation susbstrat. Activation of the enzyme is aided by the presence of the enzyme NAD and FAD. Krebs cyclePerfect for glucose catabolism compound that will produce CO2 and H2O occurs in 3 stages: glycolysis, Krebs cycle and electron transport or electron trsnsport system (ETS). Of pathways of glucose penguarian pyruvic acid will be produced which would then be oxidized via the Krebs cycle or TCA cycle (tricarboxylic acid Trikarbiksilad acid =). Also known by other names that the citric acid cycle as this cycle begins a series of citric acid. Krebs cycle is sebenarntya a main road on the generation of ATP in the business group aerobic microbes or bacteria, that is through phosphorylation of oxidation. If there is oxygen, the energy of pyruvic acid will be converted through anaerobic respiration. This process will lead to the loss of one molecule of carbon and the formation of CO2 and the enzyme NADH. In the Krebs cycle, citric acid (6C) is converted into acid by carbon oksaluasetat into 4 (4C). This process is carried out by oxidation and decarboxylation reactions. Electron transport system is also a respiratory chain, an electron pathway dihsilak use by metabolism primarily by aerobic metabolism. There are also some of the reactions used by anaerobic bacteria.NADH and FADH2 produced by aerobic respiration and also by the Krebs cycle are transported and transferred kemolekul carrier (carrier molecules) contained in the lipid membrane. Carrier molecule is composed of protein and non protein. Part of a flavoprotein and cytochrome protein. While the non-protein form of quinone in the form of coenzyme Q. Pengangukutan chain was started by the oxidation of NADH and followed by the reduction of FAD to FADH and ATP will be generated. The formation of ATP by oxidative phosphorylation carried out. At the end of this chain reaction rentetat elekron Alkan aseptor react with oxygen as the electron with the help of the enzyme cytochrome oxidase. Oxygen will react with hydrogen ions to form water. The series of reactions in this system can be described as a chain on each link in the chain will be skipped electrons. At each link in the chain, in particular the reaction to release energy so that energy can be used to produce ATP. Electron transport system takes place in the cell membrane prokaryotes.Hydrolysis of starch is a carbohydrate intake in type polysaccharide. Polysaccharides are macromolecules, polymers with several monosaccharides are connected by a glycosidic bond. Beerapa polysaccharides serve as material deposits or reserves which will be hydrolyzed when necessary to provide sugar to the cells (Campbell, 2002). The ability to use sugar or elements associated with different configurations of glucose is the result of the ability of organisms to convert substrate into intermediaries as a pathway to ferment glucose (Kusnani, 2003). Based on observations of bacterial metabolism, it appears that all the bacteria, either Escerichia coli, Bacillus subtilis, and Streptococcus aureus able to hydrolyze starch. Evidence that all these bacteria are able to hydrolyze starch is a clear or transparent areas contained in the growing colonies of bacteria (results of inoculation). Ability to hydrolyze starch into glucose, maltose, and dextrin as having amylase enzyme. Starch can not be directly used, so the bacteria must first hydrolyze starch into simple molecules into the cell (Kaiser, 2005). According Hadioetomo (1990), starch hydrolysis positive test function in bacteria is characterized by apparently clear area around the streaking bacterial growth. The existence of these clear areas and organisms caused eksoenzim hydrolyze starch in agar medium. According Schegel (1994), fungi or bacteria to produce α-amylase with starch so as to describe the vast eksoenzim amilolitik between microorganisms, including bacteria Bacillus macerans, Bacillus polimexa, and Bacillus subtilis. On the observations is known that Escerichia coli has the ability to hydrolyze starch in the highest because of the clear area around the colony indicated the most widely Escerichia coli than other bacteria. When viewed from the opinion Schegel possible number of cells inoculated Escerichia coli are more numerous in the medium. So the number of cells to metabolize more and more, and clearly demonstrated the most extensive in sight. In the test of the hydrolysis of starch iodine solution used in the final stage. Iodine is used as an indicator of starch, when the medium containing starch or starch iodine is given then it will appear blue. However, if starch or hydrolyzed starch was then the colors will be clear or translucent. Color clearly indicates that the starch or starch is hydrolyzed by eksoenzim in bacteria (Hadioetomo, 1990). According to Kaiser (2005) clear or translucent in color around the bacteria after adding iodine starch can not be caused by long react with iodine. In all three bacteria were observed, all of which can hydrolyze starch, indicating that these bacteria produce the enzyme α-amylase. Fat hydrolysis Based on observations and data analysis three Escerichia coli bacteria, Bacillus subtilis, and Streptococcus aureus can hydrolyze fats, and which has the highest capacity to hydrolyze fat is Streptococcus aureus. This is evident from the intensity shown in red beneath the growth of Streptococcus aureus bacteria. This indicates that the amount of lipase enzyme produced by this bacterium is greatest when compared to other bacteria. Ability of the enzyme lipase in the fat molecules break into fatty acids and glycerol, at most. S. aureus is a place to live normally live on the face and cause acne for patient generally is supporting evidence that S. aureus hydrolyzes the optimum in fat as an energy source for cell growth and development. According Gaman, et al (1981) fat is a mixture comprising trigleserida 1 glycerol molecule bonded to 3 fatty acid molecules. Fat has such properties: insoluble in water, when heated will be changes in the melting point, smoke point and flash point, as well as plastic and easily changing shape when under pressure, may develop rancidity, and the reaction with alkali to form soap and glycerol. Lipase enzyme can hydrolyze fats and break into 3 molecules of fatty acids and a glycerol molecule, a chemical reaction which shows hydrolysis are as follows:Hydrolysis of Proteins Based on observations and analysis of data on the medium plates Skim Milk Agar (SMA) which is used to identify bacteria that can menghidrolisa casein, three types of bacteria (Escerichia coli, Bacillus subtilis, and Streptococcus aureus) is able to hydrolyze the protein. The ability of bacteria hydrolyze proteins in a region indicated by the formation of clear / clear around the scratches (where the growth of bacteria inoculated). This is in accordance with the opinion Hadioetomo (1990) which states that a positive test is characterized by apparently clear area around the streaking organism growth. Of the three bacteria (Escerichia coli, Bacillus subtilis, and Streptococcus aureus) has an ability to hydrolyze different as indicated on the data of observations, data from observations in a sequence based on its ability to hydrolyze the protein from the highest to the lowest is Bacillus subtilis, Escerichia coli and S. aureus. Differences in the ability of protein memghidrolisis prosuksi eksoenzim possible due to a different protease enzymes. Bacillus subtilis is possible to have the ability to produce more proteases than Escerichia coli, and Streptococcus aureus. The other possibility of differences in the ability to hydrolyze proteins are bacterial cells of each type of medium was inoculated at the same time not affecting the result of hydrolysis of these proteins are characterized by differences in the number of colonies that grew on the medium. Differences in the number of bacterial cells on each type of bacteria can provide a real effect. The more the number of bacterial cells, the more cell metabolism, resulting in the clear area on the medium. Protein hydrolysis is due to enzymatic reactions. Bacteria are able to hydrolyze casein has eksoenzim, that promote the suspension (medium) would be a clear area around bakteripertumbuhan bacterial growth. Kaiser (2005) states that if the bacteria are able to hydrolyze casein has eksoenzim, then the suspension it became clear the area around the growth of bacteria. Protein is an important compound in the body of a living organism. Medium that is used to detect the hydrolysis of protein is made from skim milk mixed with agar and distilled water, which in the skim milk contains casein which will be hydrolyzed into peptides and amino acids.Bacteria do the hydrolysis of various proteins into single amino acids in order to use these amino acids for protein synthesis and other cellular molecules or as an energy source (Kaiser, 2005). In our observation, clear area formed around the bacterial growth, this is caused by casein which appear white in a colloidal suspension (SMA medium) was hydrolyzed to peptides and amino acids which results in energy used for growth and development of cell metabolism.
