Introduction:
Times have gone now where people were using magnetic storage devices and sooner or later optical storage devices will not be available. Today's computers and volumes of information require increasingly more efficient and faster methods of storing data. While the speed of integrated circuit random access memory (RAM) has increased steadily over the past ten to fifteen years, the limits of these systems are rapidly approaching . In response to the rapidly changing face of computing and demand for physically smaller, greater capacity, bandwidth, a number of alternative methods to integrated circuit information storage have surfaced recently. Among the most promising of the new alternatives are photopolymer-based devices, holographic optical memory storage devices, and protein-based optical memory storage using rhodopsin , photosynthetic reaction centers, cytochrome c, photosystems I and II, phycobiliproteins, and phytochrome. This article focuses mainly on protein-based optical memory storage using the photosensitive protein bacteriorhodopsin with the two-photon method of exciting the molecules. Bacteriorhodopsin is a light-harvesting protein from bacteria that live in salt marshes that has shown some promise as feasible optical data storage.
Why there is a need of protein based memory?
Computers have gone through their own evolution in storage media. In the forties, fifties, and sixties, everyone who took a computer course used punched cards to give the computer information and store data. Since the days of punch cards, computer manufacturers have strived to squeeze more data into smaller spaces. That mission has produced both competing and complementary data storage technology including electronic circuits, magnetic media like hard disks and tape, and optical media such as compact disks. Today, companies constantly push the limits of these technologies to improve their speed, reliability, and throughput -- all while reducing cost. The fastest and most expensive storage technology today is based on electronic storage in a circuit such as a solid state "disk drive" or flash RAM. This technology is getting faster and is able to store more information thanks to improved circuit manufacturing techniques that shrink the sizes of the chip features. Plans are underway for putting up to a gigabyte of data onto a single chip. Magnetic storage technologies used for most computer hard disks are the most common and provide the best value for fast access to a large storage space. Drives can be ganged to improve reliability or throughput in a Redundant Array of Inexpensive Disks (RAID). Magnetic tape is somewhat slower than disk, but it is significantly cheaper per megabyte.
Protein Based Memory Storage 6 that hold 40 gigabytes of data. These can be arrayed together into a Redundant Array of Inexpensive Tapes (RAIT), if the throughput needs to be increased beyond the capability of one drive. For randomly accessible removable storage, manufacturers are beginning to ship low-cost cartridges that combine the speed and random access of a hard drive with the low cost of tape. These drives can store from 100 megabytes to more than one gigabyte per cartridge. Standard compact disks are also gaining a reputation as an incredibly cheap way of delivering data to desktops. They are the cheapest distribution medium around when purchased in large quantities ( Rs 3 per 700 megabyte disk). This explains why so much software is sold on CD-ROM today. With desktop CD-ROM recorders, individuals are able to publish their own CD-ROMs. With existing methods fast approaching their limits, it is no wonder that a number of new storage technologies are developing. Currently, researches are looking at protein-based memory to compete with the speed of electronic memory, the reliability of magnetic hard-disks, and the capacities of optical/magnetic storage. We contend that three-dimensional optical memory devices made from bacteriorhodopsin utilizing the two photon read and write-method is such a technology with which the future of memory lies.
Current Vs Latest:
The demands made upon computers and computing devices are increasing each year. Processor speeds are increasing at an extremely fast clip. However, the RAM used in most computers is the same type of memory used several years ago. The limits of making RAM more dense are being reached. Surprisingly, these limits may be economical rather than physical. A 5 cubic centimeter block of bacteriorhodopsin studded polymer could theoretically store 512 gigabytes of information. Also, these bacteriorhodopsin modules could also theoretically run 1000 times faster. In response to the demand for faster, more compact, and more affordable memory storage devices, several viable alternatives have appeared in recent years. Among the most promising approaches include memory storage using holography, polymer-based memory, and our focus, protein-based memory.
Protein-Based Memory:
There have been many methods and proteins researched for use in computer applications in recent years. However, among the most promising approaches, and the focus of this paper, is 3-Dimensional Optical RAM storage using the light sensitive protein bacteriorhodopsin. Bacteriorhodopsin is a protein found in the purple membranes of several species of bacteria, most notably Halo bacterium halobium. This particular bacteria lives in salt marshes. Salt marshes have very high salinity and temperatures can reach 140 degrees Fahrenheit. Unlike most proteins, Bacteriorhodopsin does not break down at these high temperatures. Early research in the field of protein-based memories yielded some serious problems with using proteins for practical computer applications. Among the most serious of the problems was the instability and unreliable nature of proteins, which are subject to thermal and photochemical degradation, making room temperature or higher-temperature use impossible. Largely through trial and error, and thanks in part to nature's own natural selection process, scientists stumbled upon Bacteriorhodopsin, a light-harvesting protein that has certain properties which make it a prime candidate for computer applications. While Bacteriorhodopsin can be used in any number of schemes to store memory, we will focus our attention on the use of Bacteriorhodopsin in 3-Dimensional Optical Memories.
3-Dimensional Optical Memories:
Three-dimensional optical memory storage offers significant promise for the development of a new generation of ultra-high density RAMs. One of the keys to this process lies in the ability of the protein to occupy different three-dimensional shapes and form cubic matrices in a polymer gel, allowing for truly three-dimensional memory storage. The other major component in the process lies in the use of a two SJVPM’s Polytechnic
Advantages:
Clearly, there are many advantages to protein-based memory, among the most significant being cost, size, and memory density. However, there are still several barriers standing in the way of mass-produced protein-based memories. For three-dimensional memory to work, all of the molecules need to be reached without altering any other molecules. This is done with a process called two-photon interaction.
Protein based storage...is an experimental means of storing data. Using proteins that respond to light from bacteria found in salt water, a small cube can store large amounts of data. By using lasers the protein can be changed depending on various wave lengths, allowing them to store and recall data. As a result protein can be used to store enormous amounts of data using lasers to read and write binary code. With this new found technology scientists are now developing a larger more efficient storage media. The students from Fowler High School, Syracuse New York, have created this presentation with help from the Living School Book of Syracuse University and the W. M. Keck Center for Molecular Electronics to show the possibilities of protein memory.
Conclusion:
This article focuses mainly on protein-based optical memory storage using the photosensitive protein Bacteriorhodopsin. Bacteriorhodopsin is a light-harvesting protein from bacteria that live in salt marshes that has shown some promise as feasible optical data storage. The present research work is to hybridize this biological molecule with the solid state components of a typical computer.
