Chapter 3, Problem 1CT

Summary Introduction

To identify:

The domain of microbe present in the sample obtained from the hot water tank of a hospital.

Introduction:

Archaea is a group of prokaryotes, which is very different from modern bacteria and eukaryotes. These prokaryotes can survive in extreme conditions. In the extreme conditions, endospores are generated in the cells, which provide the dormant stage to the organisms; therefore, the organisms are capable of surviving in extreme conditions.

Explanation of Solution

In the given scenario, an analyst took a sample from the hot water tank of a hospital. The analyst could not culture the microbes, but after microscopic analysis the analyst revealed some results.

The microscopic studies confirmed the presence of some microbes, which contain membrane-less organelles, and ribosomes. The size of the cells obtained was 0.8$\text{μm}$ (micro meter) in diameter.

The result obtained suggests that there might be a presence of archaea in the sample. The size of archaea ranges between 0.1$\text{μm}$ and 15 $\text{μm}$ in diameter, and the microorganism obtained is of the size 0.8 $\text{μm}$ n diameter.

The sample was taken from a hot water tank, which shows the presence of microorganisms that are stable at high temperature. Archaea are thermophilic organisms that are also stable at high temperature.

Archaea are the prokaryotes that lack nucleus. Archaea contain ribosomes, but lack membrane bound organelles.

Summary Introduction

To discuss:

Analysis for the accurate determination of the domain.

Introduction:

Identification is performed to determine the target species of microorganisms. Various physical and chemical tests are performed to determine the metabolic functions, which are specific for the species of the microbes.

Explanation of Solution

“Bergey’s Manual of Systematic Bacteriology” suggests that rRNA sequencing (ribosomal ribonucleic acid) can reveal information about the classification of Archaea.

Another book “Bergey’s Manual of Determinative Bacteriology” is based on the phenotypic characteristics of microorganisms. Combining the characteristics given in this book and features studied under microscopes can determine the presence of Archaea in the sample.

“Bergey’s Manual of Determinative Bacteriology” categorizes the Archaea into four divisions on the basis of the nature of the cell wall. With the help of Gram staining, the actual class of Archaea can be obtained.

Gracilicutes are gram negative, and possess thin cell wall. Firmicutes are gram positive, and contain a thick cell wall. Tenericutes are cell wall lacking microbes and thus are termed as soft microorganisms. Mendosicutes are a special class of Archaea, also called as the archaebacteria. Archaebacteria possess unusual cell walls and the nutritional habits are also different.

Conclusion

The microbes found present in the sample obtained from the hot water tank may belong to domain Archaea. The microscopic study results suggest the presence of the Archaea, because Archaea contain ribosome, and lack membrane bound organelles lacking.

The diameter of Archaea ranges between 0.1$\text{μm}$ and 15$\text{μm}$ with the help of Gram staining; the staining of the microbes can be performed. Bacteriology can be used as reference for the determination of class Archaea.