Methionine as a Bacterial Antiseptic - PowerPoint Presentation

1. Methionine as a Bacterial AntisepticBob Moreland, Ph.D.Visiting Scientist, Wolfe LaboratoryDepartment of Microbiology and immunology, Stritch School of MedicineLoyola University Chicago

2. Why Reading Old Papers May Shed New Light1In reviewing the history of urinary tract infections and the urinary microbiome, came across this paper.Why is 105 cfu/ml the cut-off?How can methionine be a urinary antiseptic?Hypothesis: If you change the conditions in the urinary tract, can you alter the urinary microbiome/urotype?1Kass EH. (1957) AMA Arch Intern Med. 100(5): 709-714.

3. History of Urinary Tract Infection: Who was Edward H. Kass?1265 publications (6 posthumous)Did studies to establish a UTI as > 100,000 cfu/ml Showed 10-20% postmortem pyelonephritis (autopsy study) Proponent that treatment of hypertension could prevent/attenuate stroke.Mechanism of action behind toxic shock syndrome in women.Born 1918 Bronx, New York.BS, MS University of Kentucky (Biology), PhD University of Wisconsin (Bacteriology), MD UCSFHarvard faculty, staff of Boston City Hospital, 1947 to work on infectious disease research. 1Wald, N. (1990) Int J Epidemiol 19 (2): 231-232.

4. Bacteriuria and Pyelonephritis Urinary tract infections second only to respiratory infectionsPyelonephritis common at autopsy (10-20%)Renal damage due to infection even with recovery include hypertension, nephrosclerosis, toxemia (pregnancy)Pyelonephritis when symptoms present (flank pain, fever, burning w/urination), can be too late to treat (sepsis)Kass first proposed a link between bacteruria and pyelonephritis.Hypothesized counts of bacteria (urinary pathogens) would correlate with pyelonephritis.1Kass EH. (1956) Trans Assoc Am Physicians. 69:56-64..

5. Asymptomatic Infections of Urinary Tract 67 asymptomatic, untreated womenTransurethral catheterizationCount bacteria/ml urine (triplicate)Gram stainRepeat sampling 1-10 months later to see stability of count> 105 cfu/ml more likely to develop pyelonephritis.1Kass EH. (1956) Trans Assoc Am Physicians. 69:56-64..

6. Gram Stain and Bacterial CountsUROPATHOGEN GRAM STAINActinotignum schaali PositiveAerococcus urinae PositiveAlloscardovia omnicolens PositiveCitrobacter freundii NegativeCitrobacter koseri NegativeCorynebacterium riegelii PositiveCorynebacterium urealyticum PositiveEnterobacter aerogenes NegativeEnterococcus faecalis PositiveEscherichia coli NegativeKlebsiella pneumoniae NegativeMorganella morganii NegativeOligella urethalis NegativeProteus mirabilis NegativePseudomonas aeruginosa NegativeSerratia marcescens PositiveStaphylococcus aureus PositiveStaphylococcus lugdunensis PositiveStreptococcus agalactiae Positive Gram positive = Crystal violet (Purple)Gram negative= Safranin/ Carbol fuschin (Red)Kass EH. (1956) Trans Assoc Am Physicians. 69:56-64.Price et al., (2016) J Clin Micro 54(5): 1216-1223.Is a “positive” Gram Stain: Gram negative ?With 1000-10,000: 20%With 100,000 and greater: 80%Bolded organisms from Price et al., were noted in Dr. Kass’ study.

7. Bacteruria and Diagnosis of Urinary Tract InfectionsNumbers correlate with pyelonephritisUropathogens mentioned include: Aerobacter (Enterobacter), Proteus, Pseudomonas, Enterococci1Kass EH. (1956) Trans Assoc Am Physicians. 69:56-64..

8. Methionine as a Urinary Tract AntisepticProblem. Urea splitting bacteria such as Proteus and Aerobacter (Enterobacter) raise urine pH decreasing the effectiveness of methenamine.Feeding methionine lowers the pH of urine due to excretion of sulfate.Methenamine mandelate is efficacious at more acidic pHHypothesis: Feed methionine and treat with methenamine to decrease bacteria 1Kass EH, Ziai M. (1957) Antibiot Annu. 5: 80-85.

9. Methionine, 12-15g/day, urine pH may be lowered to 4.5 to 5.0.Adequate renal function, maintain for months.Chronic UTI, bacterial counts reduced to 1/1000th , sometimes eliminated.Methenamine mandelate in addition was effective in reducing bacterial counts.An active metabolite of methionine may have antiseptic properties.Methionine as a Urinary Tract Antiseptic1Kass EH. (1957) AMA Arch Intern Med. 100(5): 709-714.2Kass EH, Ziai M. (1957) Antibiot Annu. 5: 80-85.

10. A Little Bit of Metabolism1How does methionine drop urinary pH from 7.5 to 5.5?What does this do to the urinary microbiome in both the upper and lower urinary tract?Lab to do list: what is the permissible pH range of our urinary pathogens?NOTE: In older literature, Asymptomatic bacteruria may mean normal flora such as Lactobacillis and Gardnerella.Professor Kass notes bacilluria2. ICD10 code that means a urine observation of unknown origin (!).1Lemann and Relman (1959) J Clin Invest. 38(12): 2215-2223.2Kass EH. (1957) AMA Arch Intern Med. 100(5): 709-714.

11. Struvite Stones, Long Term Follow-up Under Metaphylaxis1Struvite stones: 15-34 % of all kidney stones. Women 2X MenInfection is caused by Proteus, Providencia and Klebsiella (urea splitting).n= 19 (4 men, 15 women, 54 yo (46-62). Five patients had one kidneyProteus (n = 14), Providencia (n = 3),Klebsiella (n = 2). Ampicillin and/or Aminoglykoside peri and postop 2-4 weeks. L-methionine (Acimethin 500mg) (1500 to 3000mg/day). 10 years.At Rx all patients were free of stones.Ten-year follow-up sampling urine every three months.16/19 are stone free. 1Jarrar K, et al. (1996) Ann Urol (Paris) 30(3): 112-117.

12. Recurrent UTI: Methionine versus Nalidixic Acid1Fünfstück R, Straube E, Schildbach O, Tietz U (1997) Med Klin (Munich) 92(10):574-581. .33 women chronic recurrent UTI23 Rx 3 X 500mg Acimethin (L-methionine) 26 months10 Rx Nevigramon (nalidixic acid) 21.8 monthsBacterial profile includes uropathogens (even in German)Methionine reduced bacterial number compared to nalidixic acidL-methionine is suitable to prevent reinfection with chronic urinary tract infection.

13. Are Sulfur Containing Amino Acids Detrimental to Health? Homocysteine and CV Risk

14. Hypothesis: Methionine as a Urinary Antiseptic1,2HYPOTHESIS. Using dietary L-methionine to acidify the urinary tract, monitor the change in urotype with time. Would you see a shift to Lactobacillis, Streptococcus, and perhaps Bifidobacteria.Experimental questions.What is the pH growth profile of urinary microbiome?Is it affected by biofilm formation?If one did a trial with dietary methionine and collected urine in a longitudinal study, would changes occur?Will this treat recurrent/acute UTI (42 citations in literature)Will this treat stones/stent films (2 citations)?Cardiovascular risks. NHANES study. Acute treatment?The forte of LUEREC is correlating the flora with the clinical data.1Kass EH. (1957) AMA Arch Intern Med. 100(5): 709-714.2Kass EH, Ziai M. (1957) Antibiot Annu. 5: 80-85.

15. A Lesson from Metabolism1In utero, the mammalian fetus is sterile (303). During and after birth, the human neonate becomes exposed to and colonized by large numbers of E. coli and Enterococcus organisms (108 to 1010 per g of contents). These rapidly growing, facultative bacteria metabolize the lactose present in breast milk to acetate and other short-chain fatty acids (SCFA, also known as volatile fatty acids), creating a reduced acidic environment favorable for colonization by the slower-growing, anaerobic acidophile Bifidobacterium. This acidophilic anaerobe eventually outcompetes E. coli, consumes most of the available sugar, and excretes large amounts of acetate and other SCFA (306). Subsequent neonatal exposure to microbes through diet, and the competition between these microbes for limited nutrients and specific niches, cause the colonic microbiota to diversify.CHANGE THE ENVIRONMENT TO FAVOR A DIFFERENT MICROBIOTA BY GROWTH ADVANTAGE AND EVEN SLOW GROWERS CAN COMPETE.1Wolfe AJ (2005) Micro Mol Bio Rev 69 (1): 12-50.