1. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.1 Online Counseling Resource YCMOU ELearning Drive… School of Architecture, Science and Technology Yashwantrao Chavan Maharashtra Open University, Nashik – 422222, India

2. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.2 Programmes and Courses  SEP – SBT081 – Unit 01 OC-SBT081-CP01-04 Introduction

3. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.3 Credits  Academic Inputs by Arun Punaji More. M.Sc. (Microbiology) ‏ Experience: 11 Years arunmesh@hotmail.com

4. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.4 How to Use This Resource  Counselor at each study center should use this presentation to deliver lecture of 40-60 minutes during Face-To-Face counseling.  Discussion about students difficulties or tutorial with assignments should follow the lecture for about 40-60 minutes.  Handouts (with 6 slides on each A4 size page) of this presentation should be provided to each student.  Each student should discuss on the discussion forum all the terms which could not be understood. This will improve his writing skills and enhance knowledge level about topics, which shall be immensely useful for end exam.  Appear several times, for all the Self-Tests, available for this course.  Student can use handouts for last minutes preparation just before end exam.

5. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.5 Learning Objectives  After studying this module, you should be able to:  Describe the general characteristics of Archaea.  Enlist examples of Archaea  Describe significances of some members of physiological groups of Archaea.

6. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.6 Introduction  In modern taxonomy, the organisms are divided into number of classes on the basis of rRNA sequences.  The organisms are placed, according to this taxonomic scheme, into three domain as follow: Eukarya Archea Bacteria  In previous taxonomic scheme, the organisms were divided into Eukaryotes, prokaryotes; and prokryotes were further divided into archaeacteria and bacteria.  In this presentation we will learn some interesting features of archaebacteria.

7. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.7 Archaea-1  The term “archaebacteria” is not used now a day, in the modern taxonomy, but reffered to as “Archaea”.  The “Archaea”,though share some morphological features of baceria, are distinct group of prokaryotes on the basis of their rRNA sequences.  Besides the morphological features the members of archaea also possess the almost same prokaryotic cell structure as that of bacteria with some distinct differences from the bacteria.  The Archaea is divided into two phyla: Crenarchaeota Euryarchaeota

8. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.8 Archaea-2  The phylum euryarchaeota contain three groups having different physiology such as aerobic, anaerobic, acidophilic and alkaliphilic.  Methanogens are strict anaerobic.  Halobacterium salinarum extreme halophilic and aerobic Archaea.  Thermoplasma lack cell wall and grow at high temperature and low pH.  Picrophilus is example of thermoplasma.

9. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.9 Archaea-3  Characteristics of Archaea:- The cell walls of Archaea lack peptidoglycan. Archaea reproduce by binary fission, budding, and fragmentation. No members of Archaea is known to cause disease in humans and animals. The important members of Archaea are  Methanogens  Thermophiles  Halophiles

10. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.10 Archaea-4  Methanogens:- Methanogens are obligate anaerobic microorganisms. Methanogens can convert CO 2,H 2 and organic acids into methane gas. Methanogens play important role in converting the wastes in ocean, ponds and river bed into methane. Therefore they have got industrial application in sewage treatment. The methane produced from sewage is used to generate electricity. In India, in the rural area, domestic gobar gas plant (dug gas plants) are widely used to produce methane as cooking gas.

11. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.11 Archaea-5  The Methanogens show fluorescence when expose to UV light. Fig:: Fluorescing methanogens under UV microscope

12. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.12 Archaea-6  The Archaea are also divided for the convenience of their identification into following physiological groups: Thermophiles Acidophiles Halophiles  These physiological groups are collectively called as extremophiles.  Extremophiles are defined as microorganisms which require extreme conditions of temperature, pH and salinity.

13. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.13 Archaea-7  Thermophiles:- These members of archaea can grow at temperature more than 45 ° C. Some of the thermophiles can even grow at the temperature of 80 ° C. Since the enzymes and proteins of thermophiles can remain stable above 80 ° C, they have got many industrial applications. For example, the RNA plymerase from thermophilus aquaticus is used in genetic engineering, in the polymerase chain reaction. The ability of thermophiles to grow at extremely high temperature is used to isolate and identify the thermophiles in laboratory.

14. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.14 Archaea-8  Thermophiles:- For example, the RNA plymerase from thermophilus aquaticus is used in genetic engineering, in the polymerase chain reaction. The ability of thermophiles to grow at extremely high temperature is used to isolate and identify the thermophiles in laboratory.

15. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.15 Archaea-9  Halophiles:- The halophiles have got absolute dependency on a concentration of NaCl greater than 9%. The halophiles require such high concentration of NaCl to maintain the integrity of their cell wall. Some halophiles can survive up to the 35% concentration of NaCl. Most halophiles can grow and reproduce in range of 17% to 23% of concentration of NaCl.

16. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.16 Archaea-10  Halophiles:- This capability of growing at higher concentration of NaCl is used to isolate the halophiles in pure culture and help to identify the halophiles in laboratory. The example of halophile Archaea is Halobacterium salinarum.

17. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.17 What We Learn...  The characteristic features of Archaea.  Different physiological groups of Archaea.  Natural habitats of Archaea.

18. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.18 Critical Thinking Questions  How the Archaea can grow in extreme conditions such as high temperature, high salt concentration?

19. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.19 Hints For Critical Thinking Questions  Enzymes which remain stable at high temperature.

20. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.20 Study Tips  Book Title: Title:Microbiology Author: Author: Robert W Bauman Publication: Publication: Benjamin Cummings, San Francisco  Book Title: Title: Microbiology, An Introduction Author: Author: Tortora and et al. Publication: Publication: Pearson education, Singapore

21. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.21 End of the Presentation Thank You!