Reflective journal on Awesome Microbe Carnival

Before AMC

I find a little bit confusing about the job scope of secretary, where most of the time Ee lyn was doing all the work and she didn't ask much help from me. Therefore me and Jossy felt guilty of not helping much all the time. To be honest I didn't join the preparation of AMC too much as other committee did and I felt really sorry. However, I think that trello is a good platform for us to update our progress as the other committee can access to it anytime.

During AMC
 
Me and Ee Lyn in charged of registration counter most of the time. If we realised there were some big groups of students entered, we will either ask some seniors to look after the registration counter or we take turn to go in so that we can explain our poster to them. This is because Alia and Azny were in charged of games booth, so there were only both Aisyah and Atikah to explain our poster to visitor.

On the second day, we realised our booklet is almost out of stock. Therefore we decided to keep few copies of booklets for the university that is confirm coming rather than giving it to the visitors. There was one malay visitor asked whether there is extra booklet from me as she really seems like she wanted to get more information about this carnival. However due to lacking of booklet I really felt sorry to reject her.

So far there was not much problems regarding the registration booth. But overall, I realised the most common and significant problem is that our committees did not approach visitors to explain to them more on microorganisms. Some of us just stand in front of the poster and wait for the visitor to come nearer to the poster. I can still remember there were two girls asking me question regarding disk diffusion method. Based on what I had carried out in experiment before, I told her that this method is about placing a small rounded filter paper soaked with antibiotics on the agar plate cultured with bacteria to be tested. After that we grow the bacteria and observe whether there is presence of 'zone of inhibition'. In my explanation, zone of inhibition is a transparent ring around the disk. As the growth of bacteria is indicated by cloudiness or colonies on agar plate, if the bacteria is susceptible to particular antibiotics then the area around the disk will be no bacteria growing. As a result the area around the disk appear clear.

In a conclusion, I think we need to take more initiative to introduce to the visitor more on our own field of studies. Moreover, we should have studied more latest article or updates regarding microbiology so that we could answer when they asked us questions. Also, we can tell them what is the importance or impact of microorganisms towards medical, manufacturing and food industry by relating microbes to the current issues.

Cell wall and membrane structure of prokaryotes (Part II)

4)Fimbriae and Pili
- Both made up of pilin
 
-

Fimbriae	Pili
Differences
Shorter	Longer
Help the cell to adhere to surface	Join bacterial cells for DNA transfer
Distributed evenly around the cell ( from several to hundreds)	Only one or two per cell
Similarities
·       Made up of protein pilin ·       Shorter and thinner than flagella

 

 

 

No.	Characteristics	Cilia	Flagella
1	Definition	Cilia are short, hair like appendages extending from the surface of a living cell.	Flagella are long, threadlike appendages on the surface of a living cell.
2	Number	Numerous	Less in Number
3	Length	Short and hair like organelle (5-10µ)	Long wipe like organelle (150µ)
4	Occurrence	Occurs throughout the cell surface.	Presence at one end or two ends or all over the surface.
5	Cross section	Nexin arm present.	Nexin arm absent
6	Density	Many (hundreds) per cell	Few (less than 10) per cell
7	Beating	Cilia beat in a coordinated rhythm either simultaneously (synchronous) or one after the other (metachronic).	They beat independent of each other.
8	Motion	Rotational, like a motor, very fast moving	Wave-like, undulating, sinusoidal, slow movement compared to cilia
9	Found in	Eukaryotic cells	Eukaryotic and prokaryotic cells
10	Energy Production	Cilia use ‘kinesin’ which has an ATPase activity that produces energy to perform the movement.	Flagella are powered by the proton-motive force by the plasma membrane.
11	Functions	Helps in locomotion, feeding circulation, aeration, etc.	Help mainly in locomotion only.
12	Examples	Cilia present in Paramecium	Flagella present in Salmonella

Difference between flagella and cilia



 

5) Cell wall

- Anything that is fit can pass through cell wall

- Function:

• Contributes to pathogenicity (teichoic acid and peptidoglycan)
• Classification into gram positive or gram negative
• Prevent rupture of bacteria cell
• Provide shape to bacteria
• Anchor for surface appendages ( flagella, cilia, pili)
• Withstand osmotic pressure

S.N.	Characteristics	Gram Positive	Gram Negative
1	Gram Reaction	Retain crystal violet dye and stain blue or purple	Can be decolorized to accept counterstain (safranin) and stain pink or red
2	Cell Wall	Cell Wall is 20-30 nm thick.	Cell Wall is 8-12 nm thick.
3	Cell Wall	The wall is Smooth.	The wall is wavy.
4	Peptidoglycan Layer	Thick (multilayered)	Thin (single-layered)
5	Teichoic Acids	Present in many (contribute to pathogenicity)	Absent
6	Periplasmic Space	Absent	Present
7	Outer Membrane	Absent	Present
8	Porins	Absent	Occurs in Outer Membrane
9	Lipopolysaccharide (LPS) Content	Virtually None	High (contribute to pathogenicity)
10	Lipid and Lipoprotein Content	Low (acid-fast bacteria have lipids linked to peptidoglycan)	High (because of presence of outer membrane)
11	Mesosomes	Quite Prominent	Less Prominent
12	Flagellar Structure	2 rings in basal body	4 rings in basal body
13	Toxin Produced	Exotoxins	Endotoxins or Exotoxins
14	Resistance to Physical Disruption	High	Low
15	Cell Wall Disruption by Lysozyme	High	Low (requires pretreatment to destabilize outer membrane)
16	Susceptibility to Penicillin and Sulfonamide	High	Low
17	Susceptibility to Streptomycin, Chloramphenicol and Tetracycline	Low	High
18	Inhibition by Basic Dyes	High	Low
19	Susceptibility to Anionic Detergents	High	Low
20	Resistance to Sodium Azide	High	Low
21	Resistance to Drying	High	Low