Bacillus cereus is a spore-producing rod-shaped, gram-positive bacterium. It releases toxins that result in vomiting or diarrhea. Bacillus cereus infections are self-limiting, mild, and harmless. Some strains of this bacterium are beneficial as it is used as probiotics for animals. Bacillus cereus is a food-borne bacteria. It also found in soil. It causes fried rice syndrome. Spore formation causes it to survive adverse environments including normal cooking temperatures. This bacterium is also resistant to alcohol treatment. Few strains of this bacterium produce bacteriocins used to kill the other strains of Bacillus cereus or other gram-positive bacteria. Continue reading Bacillus cereus; overall discussion
The increased rate of foodborne disease has become great concern over the world. Every year millions of people are infected with foodborne pathogens, get hospitalized and die due to the consumption of foods along with variety of foodborne pathogens transmitted onto foods. There are several bacteria that cause foodborne disease associated with various food, we consume evryday. In this context several food borne bacteria have been discussed along with the foods they found and the disease they cause. Continue reading 10 Bacteria that cause foodborne disease.
We were 5th batch both in the microbiology department and in the university. After orientation class, the first lecture of our whole university life was delivered in Room No 304 of Bangabandhu Academic Building. It was the most beautiful room in the Microbiology department. We were waiting for our teacher to enter the room. On that day we didn’t know all of our friends (total of 35 students). I only introduced with 4/5 friends. Continue reading What was the first lesson of your bachelor microbiology
Endosymbiosis is a relationship where one organism lives inside the other and both are benefited. It is thought that ancestral eukaryotic cells consumed aerobic bacteria and photosynthetic bacteria leading them to evolve into mitochondria and chloroplast respectively. Endosymbiotic theory stats that, the modern eukaryotic cells (mitochondria ) evolved in steps through inter-cooperation into cells from a nuclear line of descendants of chemoorganotrophic and phototrophic symbionts. It states that Mitochondria and Chloroplast were free-living bacteria that established residency in the primitive eukaryotic cells, eventually yielding the modern eukaryotic cell. Symbiosis is a specific type of relationship in which organisms from two different species live in a close, dependent relationship take advantages from each other. Continue reading 10 evidences prove that eukaryotic cells originated from free-living bacteria
Antibiotic resistance is increasing day by day over the world and this will cause a dramatic danger to the human civilization. It is now suspected that millions of people will die due to the increasing antibiotic resistance by 2050. Therefore, this increased resistance emphasizes the researchers to find new antimicrobial agents for combating microbial diseases. This article describes 15 antibiotic alternatives some of which may have strong antimicrobial effectiveness against microbial infection. Continue reading 15 antibiotic alternatives used against microbes
Vaccine is an immunomodulator that prevents microbial infection. The first vaccine was discovered by Edward Jenner.
The vaccine came to us through an excellent history. The concept of vaccine came from a milkmaid woman. She informed Edward Jenner that “she had suffered from cowpox and never get smallpox”. This information leads Jenner to an experiment for developing vaccine.
In 1796, he collected scrapings from cowpox blister and injected into a healthy young boy. A few days later, the boy became sick and recovered soon and never got either cowpox or smallpox. Continue reading What is vaccine? Types of vaccine.
Phage viruses have attracted a great attention recently as it is now considered one of the best alternatives to antibiotics.
Phages are the viruses that can replicate in the bacterial host cells, kill pathogenic bacterial cells, and are able to produce new lytic phages to keep pace with the mutation of pathogens. However, the replacement of antibiotics by phages in the treatment of bacterial diseases encounters several controversies because of the following reasons: Continue reading 8 controversies about phage therapy
Antibiotic resistance is now considered to be a great curse to the present world. Researcher suspected that millions of people will die due to the rapid emergence of antibiotic resistance by 2050. There are lots of reasons how bacteria become resistant to antibiotics. All the reasons can be narrowed into two part; mutation and horizontal gene transfer. In this context, the last reason belongs to horizontal gene transfer-mediated resistance and most of the other reasons are mutation-mediated resistance. Continue reading 10 mechanisms of antibiotic resistance in Bacteria
Viruses are one of the most numerous microorganisms on our earth and infect all types of cells (such as human cells, animal cells, plant cells, bacterial cells and fungal cells etc). So, viruses are interesting microbes to study for what they can tell us about the genetics and biochemistry of cellular mechanisms and about the process to develop a disease. Continue reading 20 General Characteristics of Viruses
Exotoxins are proteins produced by both gram-positive bacteria and gram-negative bacteria. They are considered to be among most toxic substances as they can easily disseminate in blood for their high solubility. An only small amount of exotoxins is enough to be a lethal dose. For example, 1mg of botulinum toxins is enough to kill 1 million guinea pigs. Continue reading 3 exotoxins that cause human disease