11 December

Tuesday 11 December, we have a group quizzes on the microbial metabolism and nutritional. Then, we proceed to the microbial growth topic. There are two type of requirement for growth which is physical requirement and chemical requirement. The physical requirement is light, temperature, pH, water activity and osmotic pressure. The chemical requirement is water,  carbon, oxygen, nitrogen, phosphorus and sulfur, special growth factor and trace element . The bacteria cannot survive in the temperature that below than their optimum temperature or the bacteria will lower down their activity in this condition. For pH factor, we have acidophile at pH range 0-6, neutrophile pH at range 6-7.5, alkaliphiles pH at range 8-11. In chemical growth, water factor importance is for dissolve nutrient and cellular functions. In oxygen factor, there are 5 types which is obligate, facultative anaerobe, obligate anaerobe, aerotolerant anaerobes and microaerophiles. Trace element need in small amout but without them enzyme cannot function. In special growth factors we are introduce on the watermelon snow by the dr. I get exited to know about this. When we step on it, the white snow turn pinkish-red. Not only the colour, but it also smells like a watermelon. The reason why it turns res is because we actually step on algae.

8 December

Enjoyfull day in 8 December, we went to yakult factory in Seremban. 

The Yakult factory in Malaysia is located in Seremban, Negeri Sembilan and it produces Yakult for the whole of Malaysia, as well as for export to neighbouring countries.. Firstly, we are have been introduced on the yakult production in a room. Yakult is a probiotic dairy product made by fermenting a mixture of skimmed milk with a special strain of the bacterium Lactobacillus casei Shirota. It was created by Japanese scientist Minoru Shirota, who graduated from the Medical School of Kyoto University in 1930. I knew the different between the beneficial bacteria and harmful bacteria . The beneficial bacteria will suppress growth of harmful bacteria, in contrast, harmful bacteria will cause intestinal putrefaction. By consuming 3 bottle of yakult per day it will increase good bacteria and reduce harmful bacteria and boosts on immune system. Yakult has high calcium with 58.8mg and fortified with vitamin B6, vitamin B12, vitamin D, Calcium and Niacin.

The variety of yakult bottle shape and size  from many country.

Yakult in medicine

Yakult in cosmetic

This is map of yakult factory  

We followed  the whole production process from a lobby on the first floor. The walls are made of glass, which makes every step of the production process clearly visible.

Friday 11 December

Friday 11 December, we have game class first before we go to lecture. Everyone need to make flashcards on the topics microbial nutritional and microbial metabolism and share it on blenspace. And we make a group crossword quizzes on website proprofs and we enjoy play the quizzes game together in the class. I learn the definition of term like Metabolism, Catabolic reactions, Anabolic reactions  , Catabolism, Anabolism and Enzymes. The mechanism of enzyme action is Active site, Enzyme-substrate complex,transformation,release the products of the reaction,the unchanged enzyme is now free to react with other substrate molecules. Factors influencing enzymatic activity is temperature, pH and concentration and inhibitors. 2 aspects of energy production which is concept of oxidation-reduction and mechanisms of ATP generation. Oxidative phosphorylation is energy released as electrons are passed to a series of electron acceptors/carriers and finally to O2 or other inorganic or organic molecules. Photophosphorylation is energy from light is trapped by chlorophyll, and electrons are passed through a series of electron acceptors. I also know Cellular respiration of Aerobic respiration,Anaerobic respiration and Fermentation . lastly on this topic I can identify the alcohol fermentation and lactic acid fermentation.

There are 2 major nutritional concern which is Source of energy and Source of carbon. In Energy sources we have phototrophs which is light as primary energy source and chemotrophs is inorganic and organic compunds as primary energy source . in Combine the energy and carbon sources, there is Photoautotrophs,  Photoheterotrophs, Chemoautotrophs and Chemoheterotrophs. 

2 December

2 December, we learnt on classification of organism. I knew how create official names for new microorganisms and identify how to plan strategy and select methods for classification and identification of microorganisms. taxonomy can be divide into 3 part which is classification , identification and nomenclature.

1)nomenclature-assignment of names to taxonomic groups in agreement with published rules

2)classification- arrangement of organisms into groups or taxon based on mutual similarity relatedness

3)identification- process of discovering and recording the traits of organisms.

Nomenclature- genus name+ specific epithet  eg. Homo sapiens or Homo sapiens

                          -general rules in nomenclature

                         1) genus name always capitalized

                         2) species name is never capitalized

                         3) species name is never use without the genus name

                        4) genus name may be used without species name

                        5) genus and species are always italicized

                        6) first timeà spell out, thereafter àabbreviated

                        7)species name never abbreviated

                       8)less simple genus abbreviation if different genus start with same alphabet

Stain can be identify by a name or number or letter follows by species epithet.the inspiration of name is based on shape, where it found,nutrition it uses, who discovered it and what disease it causes

There are two ways of classification which is phonetic classification and phylogenetic classification. Differential staining is gram staining, acid-fast stain, negative staining for capsule, endospore staining and flagella staining. Serology is the science studies serum and immune responses that are evident in serum. The serological technique is enzyme linked immunosorbent assay and webstern blotting. Phage typing is to determine which phage a bacterium is susceptible to bacteriophages cause lysis of bacteria that they infect. DNA based composition is expressed as % of guanine plus cytosine. DNA fingerprinting is use of restriction enzyme to produce banding pattern. Nucleic acid hybridization is when dsDNA is heated , complementary strands will separate as the H bonds between bases break and if ssDNA  are cooled, complementary strands will reunite. The southern blotting is when DNA probes are used in the hydridization process. Lastly, I knew the methods use to classify and identify microorganism after various analyses which are dichoto,ous keys and cladograms.

lecture 21 november

Today, 21 November we have lecture on the genetic transfer and recombination. Genetic recombinant refer to the  arrangement of DNA from separate group of gene . there are exchange between 2 DNA to form new combinations of genes in the chromosome. There are donor cell which is give a portion of its total DNA. In contrast, recipient ceel that receive a portion of DNA from donor cell. The part of donor DNA is incorporate into recipient DNA.

Transformation is process where the gene are transferred from donor to recipient. In Griffith experiment, the bacteria involve is Streptococcus pneumonia and it consist of two type of colonies which are smooth colonies and rough colonies. The smooth colonies are capsular polysaccharide and pathogen. In contrast, the rough colonies lack of capsular polysaccharide and non-pathogenic

The mechanism of genetic transformation in bacteria is process by which free DNA is incorporate into a recipient cell and bring genetic change. Competence is the alterations in the cell wall that make it permeable to large DNA molecule.

Transductions is process where the DNA is transferred from donor to recipient via betriophage. There are two type of transduction which is generalize transduction and specialize transduction.

Plasmid involve self replicating covalently closed circular DNA molecule that can survive by own. The several type of plasmid is dissimilation plasmid, conjugated plasmid and r-factor.

Conjugation requied contact between donor and recipient cells. The F+ donor contains F plasmid and F- recipient cells do not contain F plasmid.during conjugation , an Hfr Cell can transfer chromosomal DNA into the recipient cell.

Lastly, we learn Transposons carry any type  of gene, including antibiotic resistance genes. There are two type of transposons which are insertion sequence and complex transposon. Have g good Friday J

lecture 18 november

Today is 18 November , we have lecture on the mutation. Mutation is a sudden random change in genetic material of a cell that potentially can cause differ in appearance or behavior from abnormal type. We have two type of mutation which are base substitution and frameshift . in base substitution we have silent, missense, and nonsense. In frameshift mutation we have insertion or deletion and shift in reading frame.

Silent mutation is an alteration in a DNA sequence that does not result in an amino acid change in a polypeptide.

Missense mutation is a change in the first or second base and lead to significant changes in protein.

Nonsense mutation is change from codon for an amino acids to stop codon.

Frameshift mutation is a type of gene mutation where in the addition or deletion of nucleotide causes a shift in the reading frame of the codons in the mRNA.in base insertion, the addition of one or a few bases to triplet sequence in DNA. Base deletion is loss of one or a few bases that can cause frameshift mutation.

Mutagen is an agent that cause an increase in number of mutants in the population. There are four type of mutagens which are base analogues, chemical mutagen, radiation and intercalating agents.

Base analogues substituted a standard base during replication which appear in daughter cells in a later geeration.

Chemical mutagens is a substance that can alter a base that is already incorporated in DNA and change its hydrogen bonding specificity

Radiation have two type which are ionizing and nonionizing. Ionizing is more powerful form short wavelength rays while nonionizing is UV radiation at 260 nm is the most effective as a lethal agent.

Intercalating agents is planar with 3 ringed molecules whose dimensions are equivalent to purine

There are two kind of identifying mutants which is nonselectable and selectable. Positive selection is deselection is done by rejecting unwanted parents while negative selection is selection cells that are unable to carry out certain function and it use replica technique.

    Lasty, we learn on Ames test to identify carcinogens . many mutagen are carcinogens . assume that a mutant can revert to wild type in the presence of a mutagen. 

14 november 2014

Today, 14 November 2014 . We have class in the evening with heavy rain outside. But today , all of us had lots of fun at Shah Alam. So we are so tired and sleepy in the class . ahaha. We continue our lecture in regulation of gene expression in bacteria. 

There are 2 modes of gene expression which are constitutive expression and inducible expression. Major modes of regulation is to control the activity of preexisting enzyme and control the amount of enzyme synthesized . Allosteric enzyme have 2 binding sites. Active site is substrate binds and allosteric site is inhibitor binds. In regulatory protein, binds DNA at promoter of regulated gene, the repressor block transcription and activator encourage transcription. In environmental sensor is small molecule and actives or inactivates regulatory protein.

Besides that, we also learn, Enzyme repression which is response to abundance of end-product and mediated by repressors. Corepressor controls enzyme synthesize. Inducible enzyme is enzyme synthesizes in the presence of inducer. Operon is a group of coordinately regulated structural genes with related metabolic functions and the promoter and operator sites that control their transcription. Promoter is the region of DNA where RNA polymerase initiates transcription. Operator is the region of DNA adjacent to structural gene that control their transcription.

If inducer absence, no mRNA synthesized and no enzymes. If trypotophan is present, the repressor becomes active and binds operator site. Inducer present the enzyme synthesis induced. If no lactose is available, no need enzyme to produce.

Happy Friday prof. :*