Contents

Acknowledgement

Abstract

Introduction

History

Classification

Nomenclature

Antibiotic production

o Importance of limited use

o Measures for controlling antibiotic resistance

Summary

Discussion

Conclusion

References

ACKNOWLEDGEMENT

I wish to record my deep sense of gratitude and indebtedness to Almighty God for

supporting me in every walk of life and making me capable seeing dreams and

ultimately strive hard to achieve it.

I would like to take this opportunity to thank all the people in my life who have helped

me in completing third project and providing me with their abled support.

I owe my gratitude to the faculty and staff members of Hamdard Public School .Our

honorable Additional Secretary, Mr. Samar Hamid, and Madam Principal, Mrs. Zakia

Majid Siddiqui, who have always been a source of inspiration for us.

I owe special sense of gratitude to our Biotechnology teacher, Mr. Khalid Anwer, for his

learned suggestions and encouraging attitude. I am equally thankful to our Laboratory

Assistant, Mr. Anwer for providing me necessary aids during this project.

The internet services have been an immensely important part of my project in providing

all the necessary details, articles, information and pictorial representations made use of

in this project.

My sincere thanks are to my friends and classmates Sonam, Anam, Varsha and

Shafaque for their valuable suggestions, constant support and encouragement to do my

best.

I would be failing in my duty if I do not acknowledge the indebted support of my family

members. I thank my beloved brother who lend a helping hand in completing this project

as well as my parents who have always stood by me in every right decision.

This project has only been able to be completed due to the trust, well wishes and

unending support of all the people associated with me.

AQSA FATIMA

XII-B2

ABSTRACT

Broadly defined, antibiotics include a chemically heterogeneous group of small organic

Molecules of microbial origin that, at low concentrations, are deleterious to the growth or

metabolic activities of other microorganisms. That soil is rich in microorganisms capable

of antibiotic synthesis is well accepted, but the frequency with which synthesis occurs at

ecologically significant levels in nature has been much less clear. Over the past decade,

however, genetic and molecular techniques, coupled with sensitive and bioanalytical

assays and equipment, have been applied to demonstrate conclusively that

microorganisms synthesize a variety of antibiotics, even under field conditions, in the

rhizosphere (that portion of the soil enriched in carbon and energy resources released

by plant roots). These antibiotics can contribute to microbial competitiveness and the

suppression of plant root pathogens, and the bacteria that produce them are therefore

of considerable interest as a practical means of plant disease control. More generally,

the techniques used to understand the role of antibiotics in the rhizosphere are

applicable to other habitats where mechanisms of microbial antagonism or the

production of bioactive metabolites are of interest.

When used together, the bioanalytical and molecular approaches are complementary,

allowing the detection and quantification of metabolites produced in situ as well as an

evaluation of their activity, and hence their ecological significance. The direct detection

of a metabolite provides irrefutable evidence that the genetic and physiological

potentials for its synthesis have been met, and the amounts recovered are in part a

function of the net rates of synthesis and turnover under particular experimental

circumstances. Direct measurements are most informative when the identity and

physical properties of the metabolite are known so that procedures for extraction can be

optimized, and are of value in assessing the relative amounts present over a range of

conditions or in monitoring persistence and dissemination in the environment. Even

when the structure is known, sensitivity of detection is likely to be the single most

limiting factor to the direct analysis of metabolites produced in situ. The comparatively

large sample sizes from which metabolites are extracted generally preclude direct

analyses of substances produced by localized populations in spatially restricted sites in

soil or on plant surfaces. Molecular approaches offer highly sensitive but indirect

alternatives to the direct analysis of bioactive metabolites produced in situ. These

techniques detect either the potential for synthesis as inferred from the presence or

expression of biosynthetic genes, or an activity attributable to the presence of the

metabolite itself. For example, introduced and indigenous antibiotic-producing strains

can be detected and enumerated by using probes and primers based on unique DNA

sequences within genes specific for antibiotic biosynthesis. Such sequences also have

been applied to access novel biosynthetic genes directly from soil without the need for

culturing. Reporter gene systems (described elsewhere in this volume) can be used to

monitor the transcription of antibiotic biosynthesis genes expressed in situ. When the

impact of metabolites on other organisms is of primary interest, as when antibiotic-

producing agents are introduced for purposes of biological control, bioremediation, or

bio fertilization, antibiotic-nonproducing mutant derivatives are indispensable in

distinguishing between effects due specifically to the antibiotic and those attributable to

other activities of the introduced agents. This project reviews factors known to affect the

production, activity and detection of antibiotics in situ, discusses methods for extraction

and quantification from soil and plant materials, and describes approaches to detecting

biosynthetic genes, their expression, and the effects of synthesis in soil habitats.

Research until now has focused mainly on the activities of a few bacterial genera

producing compounds of known structure, but the techniques that have been developed

may be applicable to diverse taxa producing structurally undefined bioactive metabolites

as well.

Summary

From the data presented here it would appear widespread use of antimicrobials in both

inpatient and outpatient settings has been associated with the emergence of antibiotic

resistant microorganisms. Bacterial strains that have been susceptible to all

antimicrobial agents for decades have now developed resistance not only to those

classic therapies, but to newer agents as well. Other organisms have developed

resistance to new antimicrobials almost as soon as the drugs have been marketed, if

not earlier. Organisms that are resistant to several different groups of antimicrobials

have become more prevalent in recent years. Antibiotic resistance has been a concern

in the medical community since the 1950s, when an increase was documented in

colonization and infection rates of penicillin-resistant Staphylococcus aureus in

hospitalized patients. In March 1991, the Alabama Department of Public Health (ADPH)

distributed a document, “Position Paper on the Control of Methicillin-resistant

Staphylococcus aureus in Hospitals and Long-term Care Facilities”, to the acute and

long-term care facilities in Alabama. As there continues to be an evolution of knowledge

concerning antibiotic resistance, this document has been written to update the 1991

document and to incorporate the present standards of care. As the need arises, it will be

revised.

A rapid increase in the occurrence of vancomycin-resistant enterococci (VRE) reported

in United States hospitals has generated concern comparable to that observed when

the methicillin-resistant Staphylococcus aureus (MRSA) problem was first recognized.

In addition, the first clinical strain of vancomycin-resistant staphylococcus aureus

(VRSA) has recently been documented in the United States. In September, 1995, the

Centers for Disease Control and Prevention (CDC) published the document

“Recommendations for Preventing the Spread of Vancomycin Resistance,

Recommendations of the Hospital Infection Control Practices Advisory Committee

(HICPAC)”. While this valuable CDC document addresses prevention and control issues

in the acute care setting, it does not provide guidance for management of vancomycin

resistance in other healthcare settings. The purpose of this document is to update and

expand the previous ADPH position paper on MRSA and to include infection control

recommendations concerning VRE resistance in Alabama healthcare facilities/settings.

Since today’s trend is toward shorter hospital stays, more outpatient surgery, outpatient

IV therapy, and a shift to home therapy, and because a colonization/infection may not

be resolved when the patient is discharged or transferred, we have included

recommendations for nontraditional healthcare settings in an effort to prevent and

control antibiotic-resistant organism transmission.

Preventing and controlling the spread of all potential antibiotic-resistant bacteria in a

variety of healthcare settings will require a coordinated, conscious effort from all

individuals participating in the healthcare delivery system. Elements of this effort will

require: (1) instituting a system for surveillance of clinical antimicrobial susceptibility

summary reports by location and risk, (2) prudent use of antibiotics, (3) early detection

and prompt reporting of MRSA, VRE, and other epidemiologically important antibiotic

resistant organisms by clinical microbiology laboratories, (4) immediate implementation

of Standard Precautions and other appropriate infection control measures with specific

emphasis on hand hygiene (to include monitoring of healthcare worker adherence) to

prevent further spread, (5) implementing protocols for removal of invasive devices when

they are no longer needed, (6) educating healthcare staff, as well as the general public,

regarding the problems of antibiotic resistance, (7) meticulous communication between

healthcare facilities/settings, and (8) incorporating the concept of infection control and

prevention of transmission of infections into the healthcare facility’s/setting’s safety

culture.

Discussion

Since the discovery of penicillin in 1929 by Alexander Fleming the importance of

antibiotics as chemotherapeutic agent has been increasing year after year. More than

800 antibiotics are known though only few of them have a therapeutic importance. The

study of the biosynthetic pathway of many antibiotics have served as a way to design

new pathways and products.

Penicillin production can be studied as an example for the antibiotic world because it

was the first antibiotic produced on a large scale and also because today it is the one

most commonly used in the treatment of human infectious disease around the world. In

addition many of the techniques used for the industrial production of penicillin have

served as a model for the industrial production of other antibiotics or secondary

metabolites.

Traditionally increase in the production of antibiotics has been obtained using classical

improvement methods which have given good results and the use of these methods

have allowed researchers to improve the strains and the production processes.

However over the last few years molecular biology techniques have been implemented

in order to increase final antibiotic production and also to obtain products that are not

naturally synthesized.

After approximately 20 years of gene manipulation there is still one question open. Can

the DNA Recombinant technology improve natural evolution or simply make it go

faster? Since industry still uses classical mutation and screening methods to select for

better producing strains, molecular biology can probably serve as an additional tool to

improve strains which must be combined with the classical improvement techniques to

get the better result.

Conclusion

The emergence and spread of resistance to antibiotics among common pathogenic

bacteria is an important healthcare concern. Today, the magnitude of the problem has

become so great that it is threatening to reverse the scientific progress made so far.

Several factors contribute to the problem including misuse on the part of physicians and

patients, widespread use of antibiotics with high resistance potential, use of antibiotics

as animal growth promoters and in household products. Antibiotic resistance, especially

the development of bacteria resistant to multiple drugs, is a rapidly growing global

problem. Diverse factors, including patient’s expectation, over-the-counter availability of

antibiotics, rampant use of antibiotics with high resistance potential and use of

antibiotics as growth promoters in animals contribute to the problem. Effective strategies

to control antibiotic resistance are:

• Increasing public awareness through public education campaigns

• Promoting prudent use of antibiotics by health professionals

• Restricting the use of antibiotics with high resistance potential

• Checking over-the-counter sale of antibiotic

• Discouraging the use of antibiotics in animal husbandry and household products

• Formulating evidence-based guidelines for the treatment of common infections

• Surveillance at local and national level to assess the magnitude of the problem and

effectiveness of interventions.

Interventions may have limited effect as long as other regions of the world continue to

misuse antibiotics, select for resistant bacteria and spread them. Therefore, we must all

join hands in this fight to return to the world of susceptible microbes.

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BIODATA

NAME-: AQSA FATIMA

CLASS-: XII-B2

FATHERS NAME-: RAFEEQUDDIN

MOTHERS NAME-: SHABEENA RAFEEQ

ADDRESS-: RZ-605, 4TH FLOOR, STREET 21, TUGLAKABAD EXTN, NEW DELHI.

MOBILE NUMBER-: 9891393915, 9718482523