As such, it has numerous biomedical, biotechnological and agricultural applications. Halotolerant microorganisms are of considerable biotechnological interest. Chitin has proved useful for several medicinal, industrial and biotechnological purposes. Aqueous biphasic systems are used during downstream processing mainly in biotechnological and chemical industries. Advancement in biotechnological techniques has opened many possibilities for breeding crops. DAAO also plays a role in both biotechnological and medical advancements. Bhatia holds a number of patents for both clinical and biotechnological applications of engineering principles. Heterologous gene expression is used in many biotechnological applications, including protein production and metabolic engineering. The archaeal isolates can be a source of haloalkaliphilic enzymes for biotechnological applications. The enzyme consists of highly active proteins of biotechnological origin not based on protein hydrolysis. Indeed, the cultivation of plants may be viewed as the earliest biotechnological enterprise. This conversion is the basis of a potential biotechnological route to the commodity chemical 1,2-propanediol. Purple phototrophic bacteria generate interest due to their biotechnological applications. It is used for medical, engineering, biotechnological, physics, materials science and Earth science research. Many other substances not previously available in large quantities are now produced by biotechnological means.